The Russell Stannard Questions: Part Four

There are many Big Questions in science, many of which go back to the ancients, even back into prehistory in all probability. One of the best modern set I’ve found recently were sidebars in a book by Emeritus Professor of Physics at the Open University, Russell Stannard. These are my answers, thoughts and commentary to those Big Questions. Many readers might have ‘fun’ trying to come to terms with these in their own way based on their own worldview.

Continued from Part Three.

Q. Why is there no evidence for the existence of magnetic monopoles?

A. Just like theory suggests there should be one heck of a lot of antimatter around, theory also suggests that magnetic monopoles (magnets with only a north pole or a south pole) should be in abundance. That fact that we do not see magnetic monopoles is given as evidence for cosmic inflation, which, due to extreme expansion, diluted the number of magnetic monopoles down to such a very few per volume of space that as far as our volume of space is concerned, magnetic monopoles are as rare as hens’ teeth. Inflation ‘explains’ why we have no evidence for the existence of magnetic monopoles, but only of course if you accept that inflation actually happened, and there was nobody around to cover that event and report it on CNN.

Q. Is it possible to account for the values of the parameters featured in the Standard Model?

A. No. One cannot determine what the values of the physical parameters should be for the particles in the standard model of particle physics from first principles. You cannot calculate from scratch what the mass or the charge, etc. of an electron, proton, neutron, etc. should be. The values can only be determined experimentally, and having done that, determine that there is no rhyme or reason to what those values are. There is no theory that explains why a proton has a mass nearly 2000 times that of an electron, for example, and not some other value.

Q. Is there a Higgs particle?

A. Apparently that has been confirmed by the Large Hadron Collider (LHC).

Q. How are we to account for the masses of the particles?

A. The masses of the particles cannot be calculated from first principles and can only be determined experimentally. Having done that, explaining why the particles have the value they do is apparently explained by resorting to the Higgs Boson and Higgs Field which does the trick. I gather the analogy is that all things Higgs are akin to a mass of people at a party randomly placed, but when a famous particle like an electron enters the room, the mass of people are no longer randomly placed but crowd around the celebrity electron and hinder its passage across the room. That hindrance, like treacle placed in its path, slows the particle down, or as we interpret it, gives the particle mass.

Q. Does supersymmetry hold and if so, why have we not as yet seen any of the supersymmetric partners?

A. Supersymmetry (SUSY) is one of those dearly beloved concepts that could, if confirmed, put the icing on the cake for string theorists. SUSY basically suggests for every force particle there is a corresponding ‘kissing cousin’ matter particle and for every matter particle there is a corresponding ‘kissing cousin’ force particle. IMHO, string theory confirms the idea of GIGO – [string] garbage in; [supersymmetry] garbage out. The garbage out is SUSY, and, as if confirming that garbage, there has been no verification of SUSY at all. The supersymmetric partners haven’t been detected – they are conspicuous by their experimental absence. Why? Because SUSY is garbage and SUSY is garbage because string theory is garbage.

Q. Does the world-in-itself exist between our discontinuous observations?

A. This is a case of does the Moon exist even if no one is looking at it. Presumably, the answer is yes, even if the observer is just phytoplankton that absorbs photons reflected off the lunar surface. Presumably water must be observing the Moon as it does its tidal thing, a thing it wouldn’t otherwise do if the Moon wasn’t there. So hairy issue number one is what exactly is an observer? An observer can be anything. An electron observes another electron when the two come in close proximity and repel each other. Hairy issue number two is how does the Moon know it is being observed? It can’t, therefore it cannot respond to a state of non-observation by vanishing. What about software? Do those video game characters exist when the game isn’t being played and sitting on your shelf? If we’re simulated beings in a Simulated (Virtual Reality) Universe and the Supreme Programmer leaves the room and does not observe us, presumably we keep on keeping on. So the answer is that the world-in-itself exists whether real or simulated. If real, well the world-in-itself (i.e. – the Universe) got along very nicely before there were observers as we traditionally define them and we traditionally define them as living things that react (observe) to their surroundings. The simulation exists as long as the software exists whether it’s running or not.  

Q. Is there any value in Everett’s many worlds hypothesis?

A. The Many Worlds Hypothesis (MWH) is an alternative to the Copenhagen Interpretation (CI) of quantum physics. The CI says that when faced with many possible possibilities or outcomes to a situation, once an observation is made, the many possibilities collapses down to just one outcome. For example, the value of the top card in a shuffled deck of card has 52 possible possibilities. Once an observation is made, only one of those 52 possibilities is realized. The MWH however suggests that all possibilities are realized – one possibility realized in our world; the rest in newly established worlds. So, when you observe the top card, your world divides into another 51 other worlds, each new world corresponding to each possible value of the top card that wasn’t observed when you looked. I guess there is value in that approach, but it’s sort of a sledge hammer approach. When you consider all of the forks-in-the-road the cosmos faces each and every nanosecond, well accepting the MWH means that there are multi-trillions upon trillions upon trillions upon trillions of worlds that have a really real existence somewhere out there and they are increasing at a rapid rate of knots to boot.

  

Q. Is the task of science to describe the world-in-itself, whether or not it is being observed, or must it confine itself to speaking only of our observations of the world?

A. Ideally, science tries to account for those actual observations one makes of the world-in-itself. However, there are numerous bits and pieces in scientific texts that rely on speculation and theory and what ifs and extrapolations and mathematical equations. We can’t observe inside the core of the Sun or inside a Black Hole. Nobody has actually observed an electron or a quark. There are many theoretical things we haven’t observed yet like monopoles or gravity waves or supersymmetric particles or extraterrestrials, yet they too are considered a legit part of science.

Q. How are we to understand quantum entanglement, i.e. ‘spooky action at a distance’?

A. We can’t understand quantum entanglement if the Universe is an ordered and comprehensible place. That’s why Einstein railed against it because it was ‘spooky action at a distance’ and there was no place in an ordered Universe for spooky events, but if there were spooky events, well they happened outside of an ordered and comprehensible Universe and thus weren’t understandable. Of course software can be programmed to produce as much spookiness as the programmer wants.

Q. How many dimensions are there? And why are some curled up, and others extended?

A. There are no dimensions at all. Dimensionality is a human invention, attributing magical meaning to right angles, which do have a practical value in navigating around the world and the universe. Since dimensions are mathematical constructs, and therefore not-things (you cannot detect points, length, area or volume – even the so-called fourth dimension of time - with any of your five senses) then how many dimensions there are is a pretty meaningless question.

Q. Is there an M-theory, and if so, what is it?

A. M-theory is just a consolidation of various string theories that now require even one more additional spatial dimension! IMHO, this is all a case of GIGO – garbage in; garbage out.

Q. Is there any way of proving the validity of some form of string theory?

A. IMHO string theory has no validity on the grounds that it has been examined to death over the past three-plus decades without the slightest experimental run being put on the board. Verifying supersymmetry (SUSY) is the closest string theorists can come to putting their money where their mouths are, but any hope of that has apparently gone by the boards as the Large Hadrn Collider (LHC) hasn’t verified any SUSY at all.

Q. Will we ever be able to formulate a fully satisfactory theory of quantum gravity?

A. No. Quantum gravity is the Holy Grail of physics, the Theory of Everything or TOE. It’s, to date, been another case of ‘never have so many worked so hard for so long for so little results’. The quantum is the realm of the discontinuous unclassical micro; gravity is the realm of the continuous and classical macro. They are, ultimately two entirely different sets of software running the cosmos. If the Universe were really real, a TOE should leap out of the woodwork since there would have to be one unified natural nature. The fact that there is no TOE strongly suggests that the Universe isn’t really real and does not have a unified natural nature. That is, the Universe is virtually ‘real’ and the Supreme Programmer has written two separate and apart sets of software to run it – the micro software and the macro software.

Q. Does complete understanding require more than solely physical explanations?

A. By complete understanding, one has to incorporate those seemingly nebulous things that reside within the time, thinks that seem far removed from the physical world of forces and fields and particles and actions and reactions, etc. These so-called nebulous things revolve around consciousness and the subconscious, thinking (that’s clearly a neurochemical process), memory (clearly chemically encoded), creativity, emotions (definitely chemically driven), morals and ethics, right and wrong, a soul, spirituality, free will, etc. However, all these sorts of concepts reside in the brain or in a part of the brain normally identified as the mind. Whether mind-in-the-brain, or just in or a part of the brain, the brain is ultimately composed of fundamental particles that make up atoms that make up molecules that ultimately make up your neurochemistry and thus your brain and structures within. The proof of the pudding that these so-called nebulous concepts reside in the realm of the physical is that these concepts or things can be altered by physical things – physical happenings like injury (you can be knocked unconscious) or lose consciousness in sleep; chemical things like drugs, lack of sleep, the aging process and related can have decided effects on aspects of your personality, etc.; biological happenings like disease also can have profound effects on some of those so-called nebulous things. They can also be altered by your own self, being creative and via thinking deep thoughts which is an electrochemical process (you might think ‘morals be damned, crime does pay’) and of course closely related, the lifelong learning process (as in learning and altering your learning about say morals/ethics; right/wrong) – as you learn, you may find that what you thought was crystal clear, black and white, is really murky and grey. The learning process (formal or otherwise) can have profound effects on your belief systems and worldviews. Learning clearly has foundations in neurochemistry.    



It’s About Time – For a Change: Part One

Introduction: The real nature of what we call ‘time’ is one of the Big Questions. It’s been debated ever since humans evolved thought and language. That puzzlement remains true to the average person today, although ‘time’ has become the professional subject or province of philosophers, metaphysicists, and theoretical physicists, not to forget many a science fiction author! Here’s my two cents worth – ‘time’ is an illusion!

What Is Time? Time is, IMHO, an illusion. Time has no real independent existence – it can’t stand by itself. If you removed all the matter and energy from the Universe, would there be left anything we could address as time? Time is just our way of keeping track of, and measuring rate of change in matter and/or energy. If nothing ever changed it would be nonsense to talk about time. The flow of time; the arrow of time; is just the flow of macro things changing. If everything were somehow ‘frozen in time’ – like a single frame from a film – then there is no actual time that can be discussed or measured. So we don’t in any sense measure something that is time, we measure rate of change and call that time.

Actually you measure rate of change by another rate of change. For example, the rate of change from birth to death is usually measured by the rate of change in position of the Earth orbiting the Sun (years and fractions of years) and rate of change of position of the Earth rotating around on its axis (days and fractions of days). Another example: The rate of change between the beginning of your lunch hour and the ending of your lunch hour is usually measured by the rate of change of the hands of a clock (sixty 360 degree sweeps of the minute hand or a 30 degrees clockwise change in the hour hand) or the rate of change in the numbers on your digital watch, say from 1:00 to 2:00. Translated, a variable or uncertain rate of change (lifespan; length of a lunch ‘hour’) is usually measured by a standard, invariable, predictable rate of change.

Now rate of change is affected by gravity – a function of mass – the greater the mass the greater the gravity and the slower things change from A to B in that gravitational field, but that slowness is only relative to someone else also measuring A to B but who is in a lesser gravitational field. A clock at the top of a tall building (lesser gravity being further from Earth’s centre) ticks at a faster rate than an identical clock at street level (which has higher gravity due to being closer to Earth’s centre). Rate of change is also affected by velocity. The faster you go, the slower things change from A to B, again however it’s relative to someone else also measuring A to B but who is moving at a lower velocity relative to you. That’s why it’s the theory of relativity! The standard example is the twin paradox – if your identical twin zooms off in a spaceship at extreme velocities to the distant stars, stops, reverses direction, and returns at that high rate of speed to Planet Earth, and to you, you’ll find your twin has aged to a far lesser degree than you. You now have grey hair and wrinkles; your interstellar travelling twin is still in her youthful prime of life.

Time vs. Time Travel: I’ll poor water on this fire at the outset by stating again that time is but an illusion. Time doesn’t exist; therefore time travel isn’t possible. Time is but a label, like your own name is but a label, and has no more reality than the label ‘Wednesday’. We just arbitrarily call every 7^th ‘day’ Wednesday, but you can no more hold Wednesday in your hands and you can time. Time, repeating myself, has no independent reality. You can’t assign any physical properties to the concept. I mean time isn’t a solid, it isn’t a liquid, and it isn’t a gas. Time has no size, weight, colour, texture, density, it doesn’t vibrate or have a wavelength, ditto no odour or flavour, it has no temperature or pressure, it doesn’t consist of any known combination of known forces and/or elementary particles, it corresponds to no known element or compound. You can’t pour time into a bottle and store it; you can’t confine time in a force field or in a prison cell or trap it on a piece of sticky fly paper. Therefore, if time has no substance, one can not actually travel through time.

What we perceive as ‘time’ is, again repeating myself, nothing but change – change in our environment; in our natural world; in our mechanical devices; and even in ourselves and associated companions (animal and human). Repeat – time is but an illusion. Change is real (cause and effect) since it involves forces and particles; energy and matter, the sorts of things that when you kick them, they kick back. We measure ‘time’ by the rate things change; rate of change is what we call ‘time’. Repeat - it’s the change (in something) that is real. 

Now on the macro scale, that is scales we interact with on a day-to-day basis, change appears to all intents and purposes to go one way (usually from a state or high order to a state of disorder) and so we view time as flowing from past to present to future – in one direction; order to disorder – past to present to future. But change in just one direction (order to disorder – past to present to future) is ultimately a function of numbers and probability. The simple illustration is to introduce a drop of ink into a bowl of water. That’s a high order situation. Now left to itself, there will be a change. The ink will disperse throughout the bowl of water. That’s a state of disorder. If a disordered uniform mix of ink and water separated all by itself into a drop of pure ink and a bowl of pure water (high order), that too is change, but we would interpret or view such an event as going backwards in time. If you viewed such a happening on film, you’d immediately conclude the film was being run backwards.

There’s a far greater probability for individual ink particles to spread out throughout a large volume than to come together in a small space. There’s lots of pathways to spread out; far fewer pathways to come together. But at the micro level, the level at which those individual ink particles do their thing, they don’t care where in the bowl of water they are. They are just as ‘happy’ to be all together as a drop of ink, as dispersed and diluted. If they do come together as a drop of ink from a dispersed/diluted state, that’s statistically unlikely, but such an event violates no laws of physics. It would be going from a state of maximum disorder to a highly ordered state; or, from an apparent future to present to past ordering. Such a change would appear for all practical purposes as apparent time travel – going backwards in time.

The catch – there’s always a catch – is while all those ink particles are defying statistical probability and undergoing apparent time-reversal, the rest of the cosmos is acting in a statistically normal way – going forward in ‘time’. So, perhaps we have a Universe where for 99.9999% of the time, 99.9999% of events within the Universe march to the beat of the standard past – present – future ordering of things. That is, in terms of change happening in a statistically probable way. While now and again tiny pockets of the Universe reverse direction, they do so at least just temporarily.  One can only defy statistically probability for only so long. So the ink particles come back together again as a drop of ink within a bowl of water – then what? They no doubt reverse direction again and proceed normally.

An analogy might be that while some individuals are winners while playing the slot machines (high order), the club still rakes in the profits from the vastly greater majority of (disordered) losers, and that no doubt the few highly ordered winners will eventually descend into a state of disorder and contribute ultimately to the club’s profit margin! It’s more statistically likely for a winner to become a loser than for a loser to become a winner.

Consider electrons. On average, any given electron has a very high probability of participating in a changing set of circumstances consistent with statistically probability. That is, the electron is moving forward in ‘time’. But if in those rare (loser to winner) occasions the changing set of circumstances goes against the grain of statistically probability, then we would view that electron as moving backwards in ‘time’. But there ultimately is no backwards or forwards in time, just change which statistically goes or moves in one general direction (order to disorder), but which can now and again, albeit briefly, go the reverse direction (disorder to order).

To belabour the point, what we call the past is change which has already happened; the present is change which is happening; the future is change that will happen.

To be continued…

Singularities: The Heart of Black Holes and the Big Bang

Singularities are fascinating objects and places, yet entirely ‘inaccessible’ in the sense that you can’t actually go there on vacation and send back a postcard, or travel to one on a government grant as a scientific expedition and report back via a peer-reviewed article in a technical scientific journal about the local environment, geography, inhabitants, etc. In a sense singularities are like Heaven in terms of accessibility. You have to rely on intuition or theory or second-hand observations as to what’s what and who’s who.  

Okay, for those readers I’ve already befuddled, I’d better tell you exactly what a singularity is! You’ve all heard of the phrase ‘Black Hole’ and not the one in Calcutta either! I refer to astronomical or cosmic Black Holes. Black Holes are ‘black’ because they have packed inside them so much stuff, so much mass, and hence so much gravity that not even particles of electromagnetic energy (photons) can escape their gravitational clutches. If photons, and that includes visible light photons, are jailed, can not pass go, can not collect $200, then they might as well as, as far as your perception of them is concerned, not exist. If what you don’t see exists, that existence is of no matter (well lots of matter actually). Translated, Black Holes are black because visible light can’t get from them to your eyeball! The absence of light is well, blackness.

So, is a Black Hole just a big lump of stuff, albeit stuff you can’t see? Well, ‘yes’ and ‘no’.  First off, we can ‘see’ Black Holes indirectly because of their gravitational influence on stellar objects we can see. I mean if you see a star whirling around something you can’t see, then the logical interpretation is that the star you can see is in orbit around something you can’t see – i.e. a Black Hole. Well ‘no’, you can’t ‘see’ a Black Hole because light from the Black Hole can’t get away from the crush of that Black Hole’s gravity.

What’s all this got to do with singularities? Well, the stuff composing a Black Hole, all that stuff that clumps together and is the centre of the massive all-encompassing gravity that prohibits the photons to escape the house (Hole) that Jack built is the Black Hole’s singularity. An analogy: The extent of the Black Hole is the extent of the Earth’s outer atmosphere; the singularity is the solid Earth proper. So think of a nebulous outer edge with a solid core of stuff in the middle. The stuff in the middle generates the intense gravity; the nebulous outer edge marks the boundary between gravity below the threshold of light escaping and light not escaping. That boundary is referred to as the ‘event horizon’; the stuff in the middle is the singularity.

Now the idea of a singularity doesn’t stop with the idea behind an astronomical Black Hole. No, a singularity is any concentration of stuff or mass that has such a massive amount of gravity as to prevent photons from leaving the gravitational well or prison so created. What’s the ultimate Black Hole – the Mother of all Black Holes? Well, if bits of our Universe can clump together to form astronomical Black Holes, then our entire Universe, when clumped together and in a relativity tiny state, would have been the Mother of all Black Holes and hence the Mother of all singularities. When was our Universe in such a state? Well, in the beginning!

Our Universe is expanding. That’s verified by direct cosmological observation. Every cluster of galaxies has such astronomically bad ‘body odour’ that every other cluster of galaxies is moving out of the vicinity quick-smart! Well actually you can’t have ‘body odour’ in space, so that’s not the real reason. The real reason is that in the beginning or once upon a time, there was some sort of explosive oomph event that started the expansion process. We call that the ‘Big Bang’ event. At the time of the Big Bang event, our entire Universe had a close encounter with, well, our entire Universe. Our entire Universe was roughly all in the same space at the same time. Translated, if you run the film of an expanding Universe backwards, you eventually get the entire contents of our Universe on collectively very intimate terms. Such a massive collection of stuff, matter, mass, hence gravity, all of the stuffs, matter or mass that the Universe possesses, well let’s just say you’d have the Mother of all singularities – in the Big Bang beginning; or anyway once upon a Big Bang time at least .  

Well surely one didn’t have this Mother of all singularities just sitting around for eons then for no apparent reason go ‘poof’ and thus have an explosive oomph moment which kick-started things off as far as our Universe is concerned. The intense gravity of the Mother of all singularities probably would have muted any oomph to begin with; the birth of our Universe stalled at the onset.

But, let’s throw some momentum into the mix. What’s the opposite of a Big Bang? It’s a Big Crunch! So let’s propose that we have this other universe which, the bits and pieces thereof, under all those mutual gravitational attractions, is slowly, ever so slowly, but ever so surely, coming together. And as it comes together, the contracting velocity gets faster, and faster, and faster. Eventually, you have this massive collection of stuff rushing together to meet at a single point in space and in time at a fantastic velocity. There is such momentum present that the contracting Big Crunch universe just can’t stop on a dime any more than an automobile going a hundred miles an hour can stop with inside of a foot of having the brakes applied. The Big Crunch at the omega point obviously forms the Mother of all Black Holes and singularities, but the sheer momentum of that contracting universe just tears the fabric of things (space and time) apart, and like a glove turning inside-out, the contraction passes through the omega point, spewing its gets out, becoming an alpha point, which is our Big Bang event and the start of our new expanding Universe.

Okay, so we have two sources that have singularities – singularities at the centre of astronomical Black Holes, and the Mother of all singularities residing inside the Mother of all Black Holes, the one that existed at the Big Bang beginning of the Universe.

We of course can’t see a singularity directly (unless you’re willing to take a one-way trip down a Black Hole, but even if you survived that and landed safely on the singularity, you couldn’t ever broadcast back your findings – that speed of light restriction that by definition a Black Hole imparts regarding sending stuff out). So, we have to rely 100% on what theoretical equations predict a singularity to be. Unfortunately, those equations, when pushed to the sorts of mass and gravitational extremes that a singularity would represent, well you get nonsense answers. Translated, if taken at face value, the equations note that the intense gravity crushes the stuff that itself is responsible for that gravity down to a point of zero dimensions and hence infinite density.

The essential problem behind this nonsense is that gravity is represented by Einstein’s Theory of General Relativity which is a classical physics smooth continuum phenomenon. That is, you can have this gravitational value, and that gravitational value, and every possible value in-between. However, tiny objects, which is what a singularity is postulated to be, is in the realm of the quantum, which is a non-continuum phenomena. Think of a staircase. You can be on this step, or the next step, but there is no step in-between the two. That is, you can have this value, or that value, but only certain other values in-between. It’s also like money – you can have a five dollar bill, and a ten dollar bill, but not a six and a third dollar bill, or an eight and three-quarters dollar bill, or even a seven or a nine dollar bill. Money and staircases are non-continuum quantum-like; money and staircases are not a smooth continuum like gravity is.  

So, to adequately come to terms with the really real properties of singularities, you need a theory of quantum gravity. Alas, despite the best efforts of thousands of theoretical physicists over many, many decades, no quantum gravity theory to be had. There’s no quantum gravity dice.

So, let’s abandon that theoretical track and go back to common sense predictions.

Either Black Hole singularities, or the Big Bang singularity, are infinitely dense and have zero volume, or they do not. If they do not (and the alternative defies common sense and is IMHO ridiculous), then singularities have a finite volume and can grow in size as more stuff is added on. You have an original tiny singularity with extremely high, but not infinite density. You keep piling stuff onto it. For a while, the density keeps on increasing, but since it can’t become infinite, there will be a point reached where further increases cease. As more and more stuff continues to be piled on, the only other option is that the size of the singularity must grow. The volume increases, and increases and increases. The upshot is that singularities can reach a size where quantum effects become negligible. Or, in other words, singularities can grow to where they aren’t quantum objects anymore, and while theories of quantum gravity might be still be useful in explaining their properties, it’s probably no longer essential. Singularities have entered the realm of classical physics.

One property of singularities I find interesting is that the stuff that eventually forms the singularity isn’t the same sort of stuff that went down the Black Hole’s throat in the first place. There’s been a phase transition of one kind of stuff to another kind of stuff. You’re quite familiar with phase transitions in your day-to-day life. There’s nothing mysterious about the concept. The most common example is steam or water vapour condensing to liquid water condensing or freezing to ice; ice melting to liquid water hence boiling or evaporating into steam or water vapour.  Apart from your division into solid, liquid and gas, there’s also plasma. Now the sort of matter that composes a singularity is probably something else yet again, a phase transition that only extreme gravity can achieve. That such a new state of matter exists is predicted by the following: If you have an ordinary matter star, and if it should happen to collide with an antimatter star, what you get is one hell of a big Ka-Boom; the annihilation of matter/antimatter into pure energy.  However, say your matter star implodes into a Black Hole with singularity. And say your antimatter star implodes into a Black Hole with singularity. Now have these two Black Holes collide. No Ka-Boom results, just a larger Black Hole! 

More Anomalies: Another Top Baker’s Dozen: Part One

From the cosmic to the quantum; from the macro to the micro; from the natural world to the human world, enigmas are everywhere. Here’s another baker’s dozen worth.

You may not be happy with the world as it is, but at least it’s orderly and makes logical sense. Walk, don’t walk, green yellow red; money trickles in, money flows out; friends and politicians come and go, enemies and stuff accumulate; the sun rises and sets, the moon waxes and wanes; people are born, people die; the days, weeks, months, seasons. and years come and go with regularity. But dig a bit deeper beneath the surface and the world and the cosmos it inhabits, is one anomalous place.

THE BIG BANG EVENT: This is no doubt a concept that nearly everyone has heard about, and swallowed hook, line and cosmological sinker because scientists present this creation of the Universe scenario as fact. It’s not fact; just the most viable theory of many theories and it has serious flaws. The accepted theoretical account of the creation or event that kick-started our Universe off not only has that event a something that created all of matter and energy, but all of time and space as well, and this creation event, to boot, all took place in a volume less than that of a pinhead (something in the realm of the quantum) and for no apparent reason at all. First there was nothing; then there was something. Wow!

At best observations that support this are indirect being made some 13.7 billion years after-the-fact. Those indirect observations that provide evidence for the Big Bang event are the fact that the Universe is expanding; the Universe has a temperature – the remnants from the hot Big Bang called the cosmic microwave background radiation (CMBR) and the amounts and ratio of hydrogen to helium. In reality there are no direct observations as nobody was present at Ground Zero all those billions of years ago.

There are really a couple of anomalies present in the standard Big Bang account. 1) You have a violation of causality – something (space, time, matter and energy) created from nothing which is a violation of several conservation laws or relationships. 2) You have a violation of pure common sense that tells you that you can not stuff the contents of the entire Universe into the realm of the quantum, something actually way less in volume in fact than a pinhead. If that’s not anomalous, I don’t know what is!

SPEED OF LIGHT: The anomaly here is that in any other scenario, velocities can be added and subtracted, except the velocity that’s known as the speed of light. Within Relativity Theory, if there is anything unintuitive it is the fact that in the entire Universe, it is the speed of light alone that is absolute or fixed, not something like space or time. It’s unintuitive in that all other bits and pieces that are in motion can be added or subtracted. So, if you are in a train that is moving at say 100 km/hour and you throw a ball at 10 km/hour in the direction at which the train is moving, to an observer outside the train, your ball is travelling at 110 km/hour. If you throw the ball towards the rear of the train, an outside observer will measure the ball as moving at 90 km/hour. If on the other hand, you shine a flashlight in the train, an outside observer will see the velocity of the resulting light beam moving at the speed of light – not the speed of light PLUS the velocity of the train, or the speed of light MINUS the velocity of the train, but at the speed of light! That’s nuts, but it’s scientifically nuts and been proven again and again in any experiment you care to devise.

QUANTUM GRAVITY AND THE THEORY OF EVERYTHING: We have the Theory of General Relativity (gravity) and Quantum Physics. Both are bedrocks of modern physics. Both are accurate to a high degree of experimental precision. Both aren’t compatible - with each other. Apparently, one (or both) of these theories must be wrong, or at best incomplete. That’s why the unification of the two (a theory of quantum gravity) is physics’ Holy Grail. However, that Holy Grail is proving as difficult to find as the Biblical Grail itself! But for the moment, it’s like the universe has two independent sets of laws – one governing the very large (gravity); one the very small (the quantum). This makes no natural or scientific sense.

We have observations of four physical forces yet no theory which unites the three quantum forces (electromagnetism, the strong nuclear force and the weak nuclear force) with the one classical force – gravity. Theory needs to be satisfied. All of the four fundamental forces should be interconnected; some sort of unification principle must be in operation that relates all four, one to the other. However, these four fundamental forces that govern the Universe show no signs of any obvious unification – well actually the three quantum ones do (known as the GUT – Grand Unified Theory), but that’s where the unification ends. Gravity remains the wallflower. If the Big Bang theory is to be proven correct as stated, scientists must of necessity come up with a viable theory of quantum gravity that is an acceptable unification of the trio of quantum forces with gravity. There is, to date, no viable theory of quantum gravity despite thousands of physicists searching for one over many generations now. Mother Nature is an anomalous bitch!

QUASARS: Quasars are ‘quasi-stellar objects’. They are ‘stellar’ because they aren’t all that large (like a galaxy). They are ‘quasi’ because they give off energy way, way, way more times greater than any star known in any astronomical catalogue. They seem to be primordial objects – they formed long ago and are now far away.  Quasars, like stars or galaxies, are their own entities and if two or more show a very close and special causality relationships then they should show identical recessional velocities (since the Universe is expanding and they are part of the Universe and that expansion). Recessional velocities are measured by an object’s red-shift. Theory identifies red-shift with velocity. However, you apparently have some observations of causality connected quasar pairs with vastly differing red-shifts (measurements of their recessional velocities). The anomaly, in an analogy, is that you can not have a runner running at 15 miles per hour holding hands with another runner running at 3 miles per hour!

MASS: There are three fundamental properties of particles (like the electron, neutrinos, the numerous quarks, etc.) and their anti-particles (like the positron). They are charge, spin and mass. As the song goes, two out of three ain’t bad, but that still leaves one out of three out of joint. In this case, it’s mass. Nobody can predict from first principles what the masses of the fundamental particles should be. That’s fairly disturbing for something as fundamental as mass. Despite the relatively large number of particles (including their equal and opposite anti-particles), there are only a few allowed values for charge and spin, values pretty much confined to the physics infield. But, for some reason, the mass (usually expressed in equivalent energy units – Einstein’s famous equation) of the various particles are not only scattered throughout the physics ballpark but are all over the city map and beyond. They take on values (albeit one value per type of particle) over many orders of magnitude without any apparent pattern or regularity or relationship between them – and nobody has the foggiest idea why, not a validly theoretical idea, or even a ‘far out’ idea. Why should mass differ so greatly from the other fundamental properties part and parcel of those elementary particles? It’s like someone just drew a few dozens of numbers out of a hat containing multi hundreds of thousands of values and assigned them to the few dozens of particles willy-nilly. Something is screwy somewhere because something so fundamental shouldn’t be so anomalous.

PHYSICAL CONSTANTS: There are constant reports of physical constants that aren’t – constant that is. Physical constants are just that – a constant. They have just one value, everywhere, every-when, and no exceptions. But apparently some ‘constants’ have more than one value depending of where and/or when. Theory and observations (if correct) are yet again not in harmony and that’s totally nuts!

TIME TRAVEL: Time travel to the past is a staple of science fiction, but surprisingly has actual viability in modern general relativity physics. In general relativity physics, time travel to the past is theoretically possible – though damned difficult in practice. However, that means that those time travel paradoxes are possible, even likely.

The anomaly are those lovable paradoxes like going back in time, say ten years, and killing yourself (which is a novel way of committing suicide), which means you couldn’t have existed to go back in time in the first place in order to kill yourself, which means you’re not dead so you can go back in time and murder yourself, etc. What kind of physics is that?

The second anomaly however is that no time travellers have been observed from our future. You would think various significant historical events would be swarming with historians and tourists from the future where time travel is possible. Nobody from our present or past has time traveled back in time and left a proof-positive calling card that we’ve ever found in the fossil record or recorded in the history books.

If something is possible, especially something as interesting as time travel, we would expect to see either people from our future in the here and now, or evidence that we’ve travelled to the past, like finding a human skeleton buried inside a T-Rex skeleton, as in inside the area where the T-Rex’s abdominal cavity would be! We don’t.

To be continued…

Three Jokers in the Deck of Physics: Part One

In physics you have four fundamental forces and four fundamental dimensions and two fundamental types of stuff with associated properties and fates. In each case you have something, the odd one out – the one that is not symmetrical – the jokers in the physics deck. What are they?

1) You have four fundamental forces of which three have symmetry.

*Electromagnetism or the Electromagnetic Force where symmetry abounds – magnetism can generate electricity; electricity can generate magnetism. Electricity/magnetism symmetry includes the positive vs. the negative; the northern pole vs. the southern pole of a magnet; attraction vs. repulsion; the negative electron vs. the antimatter twin, the positron.

*Strong Nuclear Force has symmetry in that within the nucleus of an atom, positively charged protons repel each other – protons push outwards, yet gluons keep them in their assigned place within the nucleus – gluons pull inwards: attraction vs. repulsion. 

*Weak Nuclear Force has symmetry in that particle interactions can go in either direction. Weak interactions govern radioactivity. Radioactive nuclei can obviously be created; they also obviously can come apart at the seams (radioactive decay)!

*Gravity (the Joker): Gravity is unidirectional – it is attractive only. There is no equal and opposite antigravity except in the minds of science fiction writers.

2) There are four fundamental dimensions (ignoring unverified string theory) of which three have symmetry.

You need all four dimensions (space-time) in order to specify any particular event. You cannot have a happening in space without also having it happen in time; you cannot have an event that happens in time without it also happening in a three dimensional space. Yet only three of these dimensions are symmetrical.

*Left & Right is obviously symmetrical. These movements can be undone or reversed.

*Back & Forth is also obviously symmetrical. These movements can be undone or reversed.

*Up and Down are two directions that are obviously symmetrical. These movements can be undone or reversed.

*Time (the Joker): Time is unidirectional. Time flows in one direction only, from past to present to future. There is no equal and opposite arrow of time that extends from the future to the present and onto the past. Time cannot be undone or reversed. You cannot go back in time and change what has already happened. You remember the past; you do not remember the future. 

3) There are two kinds of stuff plus the properties of stuff (like velocity, temperature, pressure and density) and the ultimate fate of stuff.

*Mass: There’s a conservation law – the conservation of mass/matter – which states that matter can neither be created not destroyed, only changed in form. Matter (mass) can be converted to other forms of matter. You can go from a solid to a liquid to a gas and back again. You can go from hydrogen and oxygen to water and from water to hydrogen and oxygen. You can fuse hydrogen into helium (which powers the Sun) which is also an example of the equivalence between matter and energy (see below) since that fusion process releases a lot of energy at the expense of a tiny bit of mass. Matter (mass) also has another form of symmetry – antimatter. Antimatter is the same as matter only with opposite electric charge (like the negatively charged electron and its antimatter counterpart, the positively charged positron).

*Energy: There’s another conservation law – the conservation of energy – which states that energy can neither be created nor destroyed, only changed in form. Energy can be converted to other forms of energy. The chemical energy inherent in petrol gets converted to the kinetic energy of motion and heat energy. The electromagnetic heat and light energy from the Sun powers up green plants, which in turn convert that solar radiation to chemical energy and ultimately your petrol as a fossil fuel, or fuel you directly as you munch on your salad.. Unlike matter however, there is no anti-energy since energy doesn’t have any charge. But I hear an objection here. What about electrical energy? Surely electricity is the flow of electrons and electrons have negative charge.

There’s another conservation law – the conservation of charge. An electron just cannot shed its negative charge and remain an electron. The electron in fact doesn’t shed its charge after electrical energy has been converted to other forms of energy. Just think of your everyday household electrical appliances. Electrical energy gets converted to sound, heat and motion in your electric razor; ditto your electric tea kettle. Your TV set receives electrical energy which is converted to light, sound, and heat. Your electric radiator converts electrical energy to heat and light; your flashlight battery converts chemical energy to electrical energy hence to light (and some heat). But sound, heat, light, motion etc. doesn’t not contain any charge. The electron’s negative charge does not literally get converted to heat or light or motion or sound. So it’s not the electron’s charge itself that’s the source of the energy in electrical energy. 

There’s one other broader conservation law which combines the conservation of matter and the conservation of energy. One of the forms matter can be changed into is energy; one of the forms energy can be changed into is matter. The symmetries between mass and energy relate as we all know from Einstein’s most famous of equations, mass equals energy; energy equals mass. Mass has often been described as ‘frozen’ energy. So antimatter should also obey that relationship. Matter can be converted to energy; antimatter can be converted to energy. If matter of one charge and antimatter of the opposite charge meet, you also get energy – a 100% conversion to energy – but there’s no longer any charge since energy isn’t electrically charged. The positive charge and the negative charge cancel.

But there’s an exception to that rule – we think. If you have a matter Black Hole, and an antimatter Black Hole, and they merge, you just get a bigger Black Hole without the ka-boom. The ‘we think’ bit is because we can’t actually see inside a Black Hole so we don’t really know what’s happening inside. For all we know, all the hell of matter-antimatter annihilation has broken loose, but the resulting conversion of matter and antimatter to pure energy is energy that still can’t escape the gravity of the Black Hole to let us know what transpired. For the sake of argument, I’ll assume real events in real time can happen inside a Black Hole; real physics can happen inside a Black Hole. 

If the merger of equal amounts of both matter and antimatter can be converted to 100% energy, then energy can create both matter and antimatter in equal amounts. And in fact the vacuum energy; quantum fluctuations, verify that virtual particle pairs – one matter, one antimatter can and are in fact created. However, these particle pairs usually then immediate annihilate again to pure energy, restoring the borrowed energy that created them back to the cosmos. More symmetry!

The properties of stuff (like temperature) can go up and they can go down (symmetry). There’s no preferred direction.

The joker comes into play when you ask what eventually happens to stuff. Left to themselves, things go from order to disorder; things cool off; eggs don’t unscramble; your automobile doesn’t un-rust, an exploded firecracker doesn’t revert back into an unexploded firecracker. That unidirectional fate of life, the universe and everything is termed entropy. Entropy is not symmetrical. The Universe ultimately ‘dies’ when everything that is in the Universe, is in the ultimate state of disorder it can achieve. Translated, that means when the Universe attains the same temperature everywhere, what’s referred to as the ‘Big Chill’ or the ‘Heat Death’ of the Universe. Don’t lose any sleep over that – it won’t come to pass for trillions of years yet.

 To be continued…

Can Black Holes Evaporate? Part One

While there is a constant transfer of matter and radiant electromagnetic energy (photons) between bodies throughout the cosmos, there are sinks, ultimate final resting places where matter/energy can retire to and be removed from the rest of the cosmos. These cosmic sinks are Black Holes. But is that retirement permanent, or can stuff re-enter the cosmic workforce? Can Black Holes evaporate? The theoretical short answer is “yes”; the long answer is “no”.

Black Holes are astrophysical objects that are so massive, that have gravity so high, that their escape velocity (some seven miles per second on Earth) exceeds the ultimate cosmic speed limit – the speed of light (186,000 miles per second). Since nothing can travel faster than the speed of light, nothing (matter and/or energy) once inside a Black Hole can ever get out again – or so the seemingly ironclad logic went.

However, that’s all according to classical physics. A physicist by the name of Jacob Bekenstein came up with the idea of applying quantum physics to Black Holes (upon a suggestion by his mentor John Wheeler – who incidentally coined the phrase “Black Hole”), and once that was done, well lo and behold, Black Holes apparently exhibited entropy, and therefore had a temperature and therefore must radiate and therefore can vomit out stuff. His ideas were mulled over and over again and finally agreed to and expanded on by the celebrated astrophysicist/cosmologist Stephen Hawking. That stuff that a Black Hole can regurgitate now goes under the name of Hawking radiation, or to give credit where credit is due it is technically Bekenstein-Hawking radiation. However, it’s usually just called Hawking radiation so I’ll stick with that convention.

Of course if Black Holes have a temperature, then they must follow the same laws of thermodynamics as any other object with temperature. One key point in thermodynamics is that energy exchanges between objects are at least partly determined by one object’s temperature compared to another object’s temperature. The temperature of a hot cup of coffee will stay hot longer the higher the temperature of the environment that surrounds that hot cup of coffee. A Black Hole’s temperature must be compared to whatever temperature surrounds the Black Hole when considering the fate of the Black Hole. So how does a Black Hole get temperature?

In retrospect, how this happens is obvious (as are all great ideas when applying hindsight).

There is no such thing as the perfect vacuum. That could only be achieved at a temperature of absolute zero where and when everything is 100% frozen stiff. Alas, such a state violates one of the most fundamental principles of quantum physics – the Heisenberg Uncertainty Principle – where it is impossible to know both the momentum and position of anything with 100% precision. If something were at absolute zero, frozen stiff and standing still, you’d know both the momentum (which would be zero) and position (at a standstill) of that something with absolute precision.

Since there is always a minimum state of energy anywhere in the Universe (something above absolute zero), and since energy and mass are equivalent (Einstein’s famous formula/equation), then that energy state, the false not-quite-absolute-zero vacuum, the vacuum energy*, can generate mass – virtual particles. However, the particles come in matter-antimatter pairs, which usually immediately annihilate and return to their former pure energy state. BUT, and there is always, a BUT – there’s an exception to the rule – that normal state of affairs can be thwarted.

The vacuum energy, that which can generate particle-antiparticle pairs, exists everywhere where existence has any meaning. Part of that existence is an area called the event horizon**, which is a concept related to the concept we call Black Holes. All Black Holes have an event horizon which surrounds them.

The event horizon surrounding a Black Hole is that somewhat fuzzy region that separates the region (below the event horizon) from which gravity rules over the speed of light, and that region (above the event horizon) where gravity’s escape velocity can’t quite dominate that speed of light velocity. I say its “fuzzy” since it’s not razor sharp, albeit nearly so.

The vacuum energy is part and parcel of the space surrounding the event horizon, above, below and spot-on. Now, what if that vacuum energy generates a pair of virtual particles, one each popping into existence above the event horizon; one below the event horizon. Then, the particles will be unable to annihilate and recombine into pure energy. One will stay within the Black Hole. The other, being above the event horizon, can be dealt a ‘get out of jail’ card. And thus, slowly, ever so slowly, but ever so surely, the Black Hole loses mass, thus energy, and evaporates.

Here’s the general picture. Black Holes can only radiate from the event horizon region which, in a very large Black Hole is going to be very cold because it’s not radiating very much, so initially only things like the mass-less photon escapes. Assuming there’s no incoming to replace the loss, the Black Hole shrinks, and as it gets smaller it warms up slightly (that’s what things that shrink tend to do) and can radiate particles with small mass – say neutrinos. When the Black Hole is tiny, it’s very warm, in a relative sense, and it can go out with a ‘bang’, maybe emitting an electron or positron which is way more massive. When there’s no more Black Hole, the vacuum energy still produces at random virtual particle pairs, but there’s no more event horizon from which to separate those virtual particle pairs and thus its all back to normal – the two annihilate and return to their vacuum energy state. That’s where the popular accounts end. End of story. The ultimate fate of Black Holes will be to evaporate via Hawking radiation, even if it does take trillions of years.

Alas, the written texts forget to mention that radiation emission (and other forms of emitted stuff) is a two-way street, not a one-way street. Black Holes can acquire stuff, as well as radiate stuff. If deposits exceed withdrawals, then Black Holes will always have a positive ‘stuff’ balance and thus won’t fully evaporate. Now this is perhaps why Hawking radiation hasn’t been observed. The tiny amount of Hawking radiation (outgoing) will be swamped by the greater, many orders of magnitude greater, amounts of incoming radiation and other stuff impacting the Black Hole.

Forget Black Holes (and their massive gravity) for a moment and concentrate on Planet Earth. Even at night, you see lots of suns – stars. You see them because they are radiating photons – particles of electromagnetic energy of which visible light is a small part. In fact you only detect a tiny fraction of visual photons because your visual detection devices (eyes) aren’t that efficient. Optical telescopes pick up a lot more of them, but they’re still just as real. You are also being hit by photons in the infrared, the ultraviolet, in radio wavelengths, X-ray photons, gamma-ray photons, etc. Though Earth’s atmosphere shields us from some of these photons (ultraviolet photons are far greater in number at the top of our atmosphere than at the bottom), you still get impacted by multi-billions of them; Planet Earth many orders of magnitude more. Some of the photons get reflected back into space; these don’t add to Earth’s energy/mass balance. Overall, there are roughly one billion photons for each and every fundamental particle with mass, like electrons and neutrinos.

Now in addition Earth (and you too) gets hit with cosmic rays, neutrinos, and cosmic dust. Even if you luck out, Planet Earth gets impacted by meteors and other outer space debris, sometimes debris large enough to not only hit the surface but do considerable damage. Planet Earth’s mass increases by many tons a day, all due to Earth’s sweeping up of the interplanetary dust and small rocks that intersect Earth’s orbit. The trillions of neutrinos that hit us are so ghostly that nearly all pass right through you and the entire planet as well despite them having a tiny amount of mass, so as far as our planet is concerned, they are of little significance. 

Now what about a Black Hole?

To be continued…

*If it helps to conceive of the concept of the vacuum energy, here’s an analogy. Think of the invisible but energetic atmosphere as the vacuum energy. Part of that atmosphere consists of invisible water vapour. But, all of a sudden, and for reasons that must have been mysterious to the ancients, part of the atmosphere undergoes a phase change into something you can see; into something solid – like a particle. You get mist/fog (clouds), rain drops, snow, sleet, hail, etc. Then, equally mysterious, those solid bits eventually undergo another phase change (evaporation standing in for annihilation) back to invisible water vapour in the equally invisible atmosphere. And so you have the invisible vacuum energy that generates particle-antiparticle pairs which annihilate back into the vacuum energy.

**The surface area of the event horizon is the same for both incoming and outgoing so there is no need to take that (non) variable under consideration.

The Nature of Gravity: Part Two

Gravity – we all feel it; it limits much that we can do or build; and we don’t understand it!

Continued from yesterday’s blog…

Presumably for there to be gravity there has to be mass (or matter), so an electron has gravity; you have gravity; the Planet Earth has gravity – and so on. But a photon, that ‘particle’ that carries the electromagnetic force, doesn’t have gravity since it can’t have any mass (because it travels at the speed of light and only something without mass can do that).

So gravity can deflect the electromagnetic force. We’ve all read about that famous experiment where the positions of stars were pinpointed that should be very near the limb of the Sun during a solar eclipse. The starlight from those stars was deflected by the Sun’s gravity and thus, during the eclipse, the stars seemed slightly out of position in the sky. This was in accordance with Einstein’s General Relativity predictions and the merger of theoretical prediction and observational reality elevated the physicist from that of a scientist known and respected by colleagues to that of international superstar known to the masses – the scientist who overthrew Newton’s Theory of Gravitation. There’s another astrophysical effect of the deflection of electromagnetic radiation by gravity, and that’s known as gravitational lensing. While predicted by Einstein, he felt it would never have any practical applications. But today’s astrophysicists have used the phenomena – that of massive (high gravity) objects in space deflecting and focusing the light (like a lens) from more distant objects behind them – to study same. It’s by this technique that the presence of ‘dark matter’ has not only been confirmed, but mapped, as ‘dark matter’ has gravity and can act as a gravitational lens!

Can gravity deflect gravity? In Newtonian physics, the gravitational force travels instantaneously. If the Sun were to somehow vanish now, we’d feel the Earth orbital effects, now. In Einstein’s Special Theory of Relativity, gravity travels at the speed of light, and thusly gravity and EM (of which light is a part) share a common bond. Thus, if the Sun were to somehow vanish now, it would be eight minutes before we’d notice Earth’s orbit being perturbed. Experiments have to date only proved gravitational influences travel at very close to light speed, but as yet, not an exact match. Close, but no cigar. Of course it’s only fair to point out that these experiments are incredibly difficult to carry out, and the final verdict is still far off.

All the four forces have particles associated with them – particles that convey the force from Point A to Point B. In the case of the electromagnetic force, it’s the mass-less photon. The strong nuclear force has the gluon. In the case of gravity, the assumed theoretical particle (it hasn’t been actually detected yet) is the graviton.

If the particle assumed to carry the gravitational force (the graviton) travels at light speed, it should be mass-less, and with analogy with the photon, be deflected by another gravitational field. If a photon passes near a Black Hole (a high gravity object), its pathway will be bent. If a graviton (say part of a gravitational wave – something predicted by Einstein’s General Theory of Relativity) were to pass near the same Black Hole, its pathway should be equally bent. If a graviton has some mass and thus travels at somewhat less than light speed, that too will show up as a change in its pathway as it passes close to a Black Hole. Equally, a graviton, if there is such an animal, should be sucked into a Black Hole if it hits the Black Hole’s bulls-eye.

It might be surprising that if gravity can deflect gravity as well as radiation, then how can gravity ‘escape’ from a Black Hole and radiation* can’t? Of course gravity is an intrinsic property of mass, and there’s certainly lots of mass in a Black Hole, so obviously a Black Hole has gravity and it’s not as if it were escaping or leaking out. Of course one could, perhaps should, argue that gravitational waves are just ripples in space-time geometry, and gravity is just geometry, and geometry can’t be sucked into a Black Hole the way matter/energy can be. Translated, gravity again is just different – it’s not a force like the other forces, it shares no commonality with electromagnetism or the strong and weak nuclear forces, its just geometry in which case there might be no need for a gravitational force particle.

An interesting side question is can light deflect light? Unfortunately, light doesn’t stand still, but what if, as a thought experiment, one fired a laser beam in one direction and another laser beam at right angles to it, but say just a fraction higher (so the two beams don’t make contact). Would the pathways of the two laser beams alter as they crossed? Would two laser beams fired off in parallel slowly be drawn together and eventually merge? How about two laser beams fired head on towards each other? I suspect the two beams would just pass through one another. To the best of my knowledge, light only interacts with light as wave phenomena, not as particle phenomena, causing constructive or destructive interference. So, two beams at right angles, or fired in parallel, wouldn’t display any particle sorts of properties – that is, deflections. Again, the photon is mass-less so shouldn’t have any sort of deflection influence on other photons. That’s my guess anyway. So…

John’s musings one: gravity is a quantum phenomenon; gravity is not a continuous phenomenon; there is a unit of gravity that can not be subdivided; the graviton is the fundamental particle that conveys the force we feel as gravity. There will eventually be an experimentally verified Theory of Everything.

John’s musings two: gravity is a consequence of geometry. Mass distorts space-time’s geometry (which would be absolutely flat in the absence of any mass) which in turn distorts how mass moves (which would be in a straight line in the absence of any geometry other than flat space-time geometry). Gravity has bugger-all to do with quantum physics and just can not be reconciled with it. There is no fundamental unit of gravity and no need for a gravity-bearing particle.

Now this mass/space-time dynamic is very interesting. Mass tells space-time how to curve or warp (which determines the geometry); space-time geometry tells mass how to move, movement which in turn alters the geometry, which in turn alters the motion, and so on, and so on. Very dynamic! It’s also very circular, sort of like the chicken and egg question.

How exactly does space-time affect the motion of mass? Well, that’s pretty straight forward – I think. It’s one of the fundamental axioms of physics that an object once set in motion, stays in motion, and travels in a straight line – unless acted on by an external force. If you hit a hockey puck across the ice, it keeps on going on (if you ignore friction) in the direction you hit it. If some other player then hits the puck, the puck (probably) changes both speed and direction. But, what if, instead, the puck hits a slight slope in the ice. The puck will change direction. Geometry has affected the motion of a mass. Geometry has mimicked a force. Or, take the unfortunate S.S. Poseidon sailing along on a smooth sea until a sudden rogue wave rudely alters her course and speed in real quick-smart time. The sea’s geometry changed, resulting in, in this case, a good cinema experience!

So how exactly does mass warp space-time? I don’t know exactly (in case you were expecting a revelation at this stage). You might think the entire concept crazy. I mean we’ve all seen the Sun and the Moon, and the Apollo astronauts have seen the Earth from afar, and we know these objects have mass and hence gravity, but have you, or the astronauts, seen any warping of space-time in the vicinity of the Sun, Moon and the Earth (unlike that – by analogy – the bowling ball on the rubber sheet illustration beloved in all physic’s texts)? Okay, there’s noting apparent to the naked eye that anything is warped, there’s no psychedelic effects apparent, no distortions, etc.  The Moon doesn’t appear as a shimmering now-you-see-it-now-you-don’t object. But then, we do have that starlight defection experiment verified during solar eclipses (tick to Einstein). Perhaps these worlds aren’t massive enough to imprint their distortions on our retinas. The more the mass, the more dramatic would be the result, and anyone who has seen long duration time exposure photographs of massive galactic-sized objects, the gravitation lens at work, witnessed the formation of Einstein’s Rings (or arcs), has certainly seen space-time warping or the pathway of light deflected by mass (tick to Einstein). 

I suspect the answer as to how exactly mass warps space-time is probably straight forward. As the Earth travels in its orbit around the sun, space (or space-time) has to give way to accommodate our planet. Or, if you toss a ball through the air, the air is displaced as the ball passes through. The air has been slightly, and briefly, warped. Or, back to the S.S. Poseidon, her sailing along on calm seas causes displacement in the ocean and generates bow waves causing the ocean’s geometry to change. The bow waves, radiating outwards (like gravity waves?) hence cause a rocking of a small rowboat far away.

So, experimental conclusions (to date): Einstein one; quantum physics/string theorists zero.

In matters of theoretical physics and accompanying mathematics, one must temper the ‘thought experiment’ results with liberal does of healthy common sense – attention string theorists. In matters of observational and verified experimental physics, healthy common sense must take a back seat to confirmed results. Despite gravitational lensing, etc. gravity (the how and the why) still seems to reside largely in the theoretical realm, and I’m sure we’d all like to see this very mysterious force emerge in the light of total understanding based on a lot more experimental data. In the meantime, in the here and now, string theorists, and those proposing models of quantum gravity, better get their experimental act together!

A further recommended reading about gravity:

Schutz, Bernard; Gravity from the Ground Up: An Introductory Guide to Gravity and General Relativity; Cambridge University Press, Cambridge; 2003:

*Actually theoretical astrophysicist Stephen Hawking showed that Black Holes weren’t entirely black; some radiation can escape from them, know known as Hawking Radiation. It’s actually a now and then quantum phenomena. Normal everyday electromagnetic radiation can’t escape from a Black Hole once trapped behind the Black Hole’s event horizon. However, the energy associated with a Black Hole, via Einstein’s famous equation relating mass and energy, can morph into virtual particles outside the Black Hole’s event horizon – that region and below of no escape.

The Nature of Gravity: Part One

Gravity – we all feel it; it limits much that we can do or build; and we don’t understand it!

Say you drop something and it falls, as you’d expect, vertically to the ground. A routine happening! You can easily explain what happened (and where and when), but can you explain how it happened, or why that something fell vertically down and not in some other direction? You probably can not.

Gravity is associated most strongly with two physicists – Newton and Einstein. Post Newton, gravity just had something (mathematical) to do with how massive objects are and how far apart they are. There was no real explanation of why or how. Gravity was just the way it was, and Newton’s Laws of Gravity were mainly predictive, not explanatory. [At least the ancients had an explanation. Objects (air, earth, fire and water) sought their natural place in the ordered scheme of things – as if they had minds of their own obeying cosmic laws. Thus, solids were at the bottom and rocks fell down because their place was with solids; water fell down but sat atop of solids; air rose to sit above water; and fire wanted to rise above the air to be with the sun, an obvious ball of fire in the sky.]

Post Einstein, gravity was just a phenomenon that was attributed to joint interactions between mass and space-time. Gravity was a property of the geometry of space. Mass distorts the shape of space-time, and so other objects move in accordance with that warped shape just like moving objects on the surface of the Earth follow the contours – the warps.

Today, physicists are trying to absorb gravity (which is a continuous phenomenon) into the now well established realm of quantum physics (which is not continuous). So far, no dice, but it’s not for lack of imaginative trying. The basic reason for trying to merge the two is that there are several things in nature that can only be adequately explained by unifying the two – primarily the singularities at the heart of Black Holes and the Big Bang.

So what exactly is gravity? Well, at first glance, gravity is obviously a force – it forces you to fall downwards or conversely, you have to apply a force to overcome it.

Traditional physics texts list four known forces at work in the Universe – gravity, electromagnetism, and the strong and weak nuclear forces. Unfortunately, gravity is pretty much now the exclusive property of Einstein’s General Relativity Theory while the other three are based around quantum physics. Physicists have as a first Holy Grail the desire to link as one the three quantum forces, or GUTs (Grand Unified Theories), and have just about succeeded – at least in combining convincingly the weak nuclear and the electromagnetic forces – electroweak theory. The second Holy Grail is to link all four into a TOE – a Theory of Everything, or in more common physics language, finding a quantum theory of gravity or quantum gravity as mentioned above.

Alas, despite intense effort (over several generations by theoretical physicists), no such link has ever been experimentally shown. The only thing to date that has achieved this TOE is the solely mathematical theory of strings, which, alas, has no experimental runs on the board some thirty years on. Even so, it takes string theory to require some ten or eleven spatial dimensions to achieve this, again something for which there are no experimental (and no common sense) evidence. It’s proving an interesting area for nerdy thinkers, but it (string theory) remains, 30 years on, theory, Theory and more THEORY!

What if one assumes the opposite (for a refreshing change)? So perhaps it just isn’t possible to relate or link gravity (hence General Relativity) to the other three known (quantum) forces. TOE is not only elusive, it’s impossible. Gravity and the other three forces can’t be combined any more than one can turn an apple into a pear. [“Heresy, heresy” I hear you cry!]

So how is gravity different? Perhaps gravity is just so different that it not only stands alone, it must stand alone.

Gravity is different #1: Unlike the other three forces, gravity has an opposite – antigravity, or in today’s cosmology, ‘dark energy’ which is causing the Universe’s expansion rate to ever increase or accelerate. You’d be hard pressed to come up with a concept of an anti-strong or anti-weak nuclear force, or an anti-electromagnetic force! What would an anti-magnetic field be? Could you have anti-light? Such concepts only induce headaches!

Gravity is different #2: Two of the three quantum forces operate over atomic (or sub-atomic) lengths. Both gravity and electromagnetism (EM) can, in theory, extend their influences to infinity. But, while EM can be blocked (at least for a while) by placing an object or insulator in front of the EM source, gravity can’t be. No known physics can block gravity. Place a sheet of metal in front of a lamp, and you block the light. Place the same sheet between you and the Earth, and you won’t start floating upwards! 

Gravity is different #3: What can gravity do that quantum forces can’t – bend light – that’s a pretty neat trick! [See below for more details.]

Gravity is different #4: Of all the four known forces, gravity is by far and away the weakest of the weak. If gravity were on the beach, gravity would get sand kicked in its face! Now you may not think gravity is all that weak while in freefall from a 12 story building roof heading for the concrete sidewalk far below, but it is – relative to the rest. [In fact it’s the electromagnetic force that terminates your 12 story fall, and presumably you!] I mean it is easier to lift up a paperclip from your desk with the entire mass of the Earth trying to stop you, than it is to separate that same paperclip from a reasonably strong magnet. In fact you could use that magnet to pick the paperclip up in the first place. Magnet one; Earth’s gravity zero! And you certainly would have to use a lot more force trying to walk through brick walls, or other solid objects, so the electromagnetic forces acting between the atoms and molecules holding them together as a solid must be pretty strong. And don’t even think about trying to pull apart the nucleus of an atom or to separate the quarks that make up a proton or neutron. No, we may think of gravity as a giant force, but it’s still the smallest of the four giants, sort of like a gnat compared to elephants.

Gravity is different #5: If string/membrane (brane) theory is right, then gravity alone of the four known forces can ‘travel’ off our brane (actually termed a braneworld) to another braneworld (and vice versa) through what is termed ‘the bulk’. The other three forces are stuck to our braneworld, and presumably, those three forces would also be glued to another braneworld. Thus, relative to the other three forces, gravity is diluted and thus is experienced as being a weaker (the weakest) force. It also explains how two braneworlds can attract one another and collide. Such a collision results in a Big Bang for each braneworld, but a Big Bang that occurred in pre-existing space and time. [Look up ‘Ekpyrotic Universe’ for the nitty-gritty details.]

Gravity is different #5 (continued): Invoking the braneworld concept and associated forces further helps to explain ‘dark matter’, which one recalls has positive gravity, yet is invisible or ‘dark’ (apparently it has no association or interaction with electromagnetic energy). Anyway, the idea is that ‘dark matter’ is in fact just ordinary matter, but on another braneworld (or in another universe – part of the Multiverse). We feel ‘dark matter’s’ gravity cause gravity can travel through ‘the bulk’ or leak between braneworlds, but we can not see ‘dark matter’ because electromagnetic energy can not travel across ‘the bulk’ that separates braneworlds. (String theory may still be, thirty years on, only pure mathematics and theory, but it can explain some real physics phenomena! Now if only someone could figure out how to slot ‘dark energy’ into this scenario, they’d be a candidate for the Nobel Prize!)

To be continued…