You and the Vacuum Energy

The electron, the proton and the quark are all entities within the realm of particle hence quantum physics. All three carry electrical charge. All three have mass. After those observations, things get interesting, or messy, depending on your point of view.

An electron has a negative charge exactly equal and opposite to that of a proton. Note: the charge is exactly equal, even though the proton has a far greater mass than the electron (some 2000 times heavier in fact, not that there has to be of necessity any relationship between mass and charge).

Now that’s strange since the electron is a fundamental particle but the positively charged proton is a composite particle, made up of a trio of quarks (as it the neutron with no net charge). The proton has two quarks each with a positive 2/3rds charge (up quark) and one quark with a negative 1/3^rd charge (down quark) for an overall balance of one positive charge. (The neutron on the other hand has one up quark with a positive 2/3rds charge and two down quarks each with a negative 1/3^rd charge, for an overall balance of zero charge – neither positive nor negative.)

Now you might suggest that an electron might be a fusion of a trio of down quarks, each with a negative 1/3^rd charge, except the electron, again, isn’t a composite particle, and the mass is all wrong for that scenario. If an electron were a composite of a trio of down quarks, each with a minus 1/3^rd charge, the electron would be thirty times more massive than it is – not something particle physicists would fail to take notice of. 

Further, the force particle that governs the electron is the photon; that which governs the quarks inside the proton and the neutron is the gluon, which further differentiates the two things – quarks and electrons. In any event, if you could have a composite particle of a trio of negative 1/3^rd down quarks, if that were the case, and it is the case, and it’s called the Negative Delta, you’d also need a composite particle that’s the fusion of a trio of positive 2/3rds up quarks for an overall charge of plus two. To the best of my knowledge there is only one such critter in the particle zoo and it’s called the Doubly Positive Delta. I’m sure you’ve never heard of these Delta particles, which goes to show how much bearing or impact they have on life, the Universe, and everything.

In case you were wondering, there would be an anti-quark of minus 2/3rds charge, and an anti-quark of a positive 1/3^rd charge, to yield an anti-proton and an anti-neutron. The anti-proton would of course have an equal and opposite charge to the anti-electron (which has a formal name – the positron). So things are equally as mysterious in the realm of the anti-world.

Question: How do you get 1/3^rd or 2/3rds of an electric charge in any event? Of course one could just multiply by three and that does away with the fractions, but that doesn’t resolve the larger issues, like for that matter, what exactly is electric charge and how does it come to be?

Presumably quarks inside of protons and neutrons, and electrons, could have taken on any old values of charge, separate and apart, but didn’t. Why? Is this evidence for a Multiverse (where anything that can happen does happen in all possible combinations); intelligent design (which does not of necessity imply a deity – just a creator, or a programmer); or just a coincidence?

Why is it so? What does it mean? Equal and opposite charges between the proton and the electron would just seem to be one of Mother Nature’s little mysteries.

But something else is odd here. The proton, as noted above, is 2000 times more massive than the electron, but if you weigh up the trio of quarks* that make up the proton, the proton should only come in at roughly 20 times that of an electron. That’s 100 times too small. So where does the other 1980 bits of mass come from? Well the gluon that holds the proton’s (and the neutron’s) quarks together, like the electron’s photon and gravity’s (theoretical or hypothetical) graviton, have no rest mass that add to the total. But the internal jiggling of the quarks and their gluon companions does add a bit more mass to the proton. Remember that motion equals energy which equals mass. Finally, that leaves the vacuum energy to fill the remaining gap.

Vacuum energy: what’s that? There’s no such state as zero energy, so there’s energy around even where you don’t expect it – like in a vacuum. If you have a finite amount of energy in a finite volume, you cannot dilute that amount of energy such that you end up with no energy present. That’s a violation of fundamental conservation laws. So this vacuum energy is present everywhere and experimentally confirmed so that’s not an issue to be debated. The next bit is to recall that Einstein’s famous equation relates the equality between energy and mass. Mass can be converted to energy and energy can be converted to mass. So this vacuum energy can produce what’s known as virtual particles, which exist for nanoseconds (actually way less than that) before recombining, going poof, and returning to the environment again as energy.

Everywhere, anywhere, all the time, these virtual particles pop into and out of existence – your basic transformation of energy into matter (mass) and back to energy again. Again, matter and energy are two sides of the same coin. A little bit of mass can create a lot of energy as the atomic bomb; a lot of energy can create a tiny bit of mass, and virtual particles are tiny, so it doesn’t take much energy to manufacture them. As you might expect, it’s cheaper (uses less energy) to create virtual ‘ping pong balls’ than virtual ‘bowling balls’, and so you get way more of the lighter particles created than the heavier ones. Further, the heavier they are the quicker they go poof again. Not that it ultimately matters but these pop-in pop-out events transpire so quickly that not even the finest and most accurate of Olympic timers could measure their duration. Quantum’s vacuum energy’s virtual pop-in pop-out is all over in the blink of a blink of a blink of a blink (add some more blinks) of an eye.

Oh, one other thing to note, when the vacuum energy creates these virtual particles, they are created in pairs – matter-antimatter pairs to be precise. Now why, when virtual particles are created are they in that form? Matter-antimatter pairs are the only viable way of returning to the vacuum energy the energy that was ‘borrowed’ to create the particles in the first place. It’s like borrowing money from the bank. You’ve got to repay it. If the vacuum energy created, say a pair of electrons, well the energy debt couldn’t be repaid since two electrons can’t annihilate each other back to pure energy. The bank’s money wouldn’t be repaid and there’d be hell to pay instead!

This constant froth and bubble is commonly called quantum fluctuations or the quantum jitters. All that activity, those virtual matter-antimatter particles, completely accounts for the missing mass – the differential between the proton’s quarks’s mass and the proton’s mass. In a similar way, presumably all matter is more massive as a result of these quantum jitters that take place in the vacuum energy, jitters which even permeate the insides of protons and neutrons. So, and I hope you’re sitting down while reading this, a large part of your mass is due to the jittery happenings of the vacuum energy!  

Given the above, I can’t help now but wonder what affect this constant froth and bubble, the quantum jitters, has on the biological body – your biological body. In theory, barring external agents like accidents, there is no real reason why we should age and die. Some diseases are obviously caused by outside agents like bacteria and viruses, but others have more mysterious origins. There are external agents like smoking, alcohol, radioactivity and ultraviolet light which can have detrimental effects. But if you exclude all nasty external agents, why would we age and ultimately snuff it?

The body, your body, my body, your pet’s body, is ultimately a composite of the fundamental particles that make up life, the universe and everything. These fundamental or elementary particles are subject to quantum phenomena. These particles have a volume for those phenomena to operate in. Even in space external to those particles, quantum phenomena operate all the time, anywhere and everywhere. The vacuum energy isn’t somewhere ‘out there’ in never-never-land. It’s everywhere including inside you from head to toe. Virtual particles are being created and destroyed inside you even as you read this, like it or not. All of this too-ing and fro-ing, the constant creation of virtual particles and hence their annihilation (literally a matter-antimatter annihilation) – energy to matter and matter back to energy – must have some sort of wear and tear on biological systems starting at the quantum or micro level and moving on up the line. If something goes wrong at the micro level, it has an obvious ripple effect on up that line to the macro level. Perhaps modern medicine should pay closer attention to quantum and particle physics!

There are probably multi hundreds of thousands of monographs exploring and explaining the workings and maladies of the human body from conception to ultimate demise; from the whole of physiology and anatomy down to the individual organ systems (i.e. – digestive system, respiratory system, nervous system, etc.); the individual organs (stomach, lungs, spinal cord); the tissues that comprise these; the cells that make up the tissues and the biochemistry that works its magic inside the cells. But I doubt if you’ll find in any medical library too many tomes on particle and quantum physics. Yet without particle and quantum physics there could be no cellular biochemistry on up to gross physiology and anatomy.

If all those quantum jitters, those now-you-see-them now-you-don’t virtual particles consisting of matter-antimatter annihilations inside you weren’t bad enough, the micro world isn’t quite through with you. You’re being bombarded 24/7/52 by millions of cosmic rays and neutrinos every second, though fortunately nearly all pass right through you as if you didn’t exist at all. However, the same can’t be said for those matter-antimatter annihilations. There’s no way I can see the creation and destruction of virtual particles (in matter-antimatter pairs) having any beneficial effect on your body, hence my postulating that these quantum jitters might have some, even if partial, effect on some diseases, infirmities, the ageing process, even ultimately death.

There’s no point is worrying about this for there’s not a damn thing you or anyone, not even your family doctor or a particle physicist, can do about it.        

The one saving grace is that the virtual energy is 120 orders of magnitude less than theory predicts, otherwise you and the Universe would be ripped apart – well actually you and the Universe would never have formed in the first place.

*There is some degree of uncertainty in the exact mass of those various quarks because they cannot be weighed in isolation. However, the estimates are probably pretty close to the mark. The error bars aren’t that great.

Parallel Universes: Part Two

Parallel universes, or alternative universes or mirror universes have had a long run of popularity in science fiction and science fantasy, in both print and visual formats. One need only look at an “Alice in Wonderland” or look no further than the “Star Trek” universe (our Universe in less than obvious disguise) to view the near endless plot variations that such parallel / alternative / mirror universes provide our heroes and heroines. Do they actually exist and do they explain anything?

Continued from yesterday’s blog…

As the collection of all universes is the Multiverse, and since the wave-particle duality is at the heart and soul of quantum mechanics, then it follows that perhaps quantum physics is just the physics of the Multiverse!

The double slit experiment can be (and has been) repeated with electrons, and neutrons and protons, etc. Same results! So, therefore, there must be virtual or shadow or ghost electrons and neutrons (or quark trios) and protons (or again quark trios). Now things get interesting! But before I get to that, David Deutsch never speculated above the level of shadow or ghost protons (or other elementary particles) as proof of parallel universes. The following extrapolations are my doing!

If there are virtual / shadow / ghost protons and neutrons, then there are (let’s just call them) ghost nuclei. Add your ghost electrons and you have ghost atoms, hence ghost molecules and on up the chain to… well, ghosts!

Now these parallel universe ghosts aren’t dead people, but people quite alive in said parallel universe. They could appear to us as dead acquaintances or even dead loved ones, but parallel universes aren’t of necessity identical copies of ours (recall the heads, tails and coin-on-edge example). Just because Mum is deceased in our Universe doesn’t mean she’s yet snuffed it in a parallel one.

These virtual or shadow or ghostly images don’t even have to be living things of course. There’s a long history of apparently sane and sober people seeing, quite unexpectedly, spectral images of non-living ‘things’, like a building appearing in a otherwise verified field-of-grass only.

There’s equally a long list of documented transient phenomena, unfortunately unpredictable and unverifiable - UFOs anyone?

Speaking of UFOs (as intelligently piloted vehicles from elsewhere and/or elsewhen), sceptics often will claim ‘it can’t be, therefore it isn’t’, where the ‘can’t be’ usually refers to the impossibility of interstellar spaceflight which would require faster-than-light velocities to make things practical and viable, blah, blah, blah…. Quite apart from the fact that that assessment is total nonsense as I’ve already elaborated on elsewhere, subluminal interstellar travel doesn’t, of necessity, violate any laws of physics, period. End of discussion. However, nobody, including me, says it will be easy, but that’s a different horse of another colour.

Anyway, if there can be some sort of now and again natural interaction between parallel universes, then it follows that an advanced technological race of beings (call them aliens if you will), might be able to artificially manipulate such ‘gateways’ and go exploring – not so much in time and space but as in crossing over from X-universe to a parallel Y-universe, which in distance terms might be as close to zero kilometres as makes no odds.

Cryptozoology is another ripe area potentially explainable in part at least by parallel dimensions. Take Loch Ness and its alleged monster, one of the most baffling of cases in all of cryptozoology. On the one hand, you’ve lots of seemingly credible witnesses with no axe to grind going back over many decades. Are they all lying, exaggerating, and being fooled or just hallucinating?  The odds of that are poor for the collective of all sightings. On the other hand, you have a relatively small and confined area offering little hiding room to a relatively large animal. It’s an area that has been combed many times with all the sophisticated technology we can muster – no animal. However, it doesn’t stretch the imagination to breaking point and beyond to suggest that in some parallel universe(s), plesiosaurs (or equivalent) still exist and that for some reason there is, albeit just a rarely now and again, some sort of harmonic resonance between that world and our world, and presto, a sighting of the elusive Loch Ness Monster.

Perhaps a most likely interaction between parallel universes is evident in our dreams. We often seemingly invent out of thin air quite unfamiliar people, places, and situations when dreaming, as well as finding ourselves in more familiar surroundings, albeit rarely something exactly parallel down to the Nth detail – at least that’s my experience. It’s maybe 90% familiar territory; never 100%.

If there is some sort of parallel universe interactions, your dreams could be, in a nebulous sort of way, a link with the lifestyle of your counterpart(s), and presumably said counterpart(s) now and again dream slightly unfamiliar scenarios that reflect your actual situations; your world and your lifestyle and relations.

It’s a sort of telepathy perhaps only achievable at the subconscious level when you’re asleep and all those day-to-day routines and constant mental activities can’t overwhelm that incredibly faint signal from a parallel universe(s).  

Now that’s not to say all dreams are parallel universe related, but some might be.

Since the double slit experiment with one photon at a time, produces interference patters 100% of the time, yet things like ghosts, UFOs, the Loch Ness Monster, even dreams, aren’t reproducible on demand, I can only conclude that it’s much easier for micro bits like photons and atoms to crossover from X-universe to Y-universe (our Universe) than it is for macro objects. But, that’s not an uncommon experience within our own world. Bacteria are vastly more common than humans – bacteria are everywhere; humans aren’t. Small things or objects can wriggle through small spaces where larger objects can not fit. It takes exceptional circumstances, an exceptional large gateway or hole between universes for a UFO or a Loch Ness Monster to make its ever so brief and unexpected appearance. So, lots of small holes or ‘gateways’ allowing lots of ghost photons (and presumably other particle types – very, very, few large holes or ‘gateways’, so actual sightings of living ghosts, etc. are very, vary rare.

Now more likely as not, it’s only a relatively few parallel universes that have a real resonance with ours. There could be other universes with physics so different that they are totally out of sight, even if not out of mind.     

Summary: The concept of parallel universes is a sound, yet novel way of explaining one of the (many) deep mysteries contained in the double slit experiment that illustrates the wave-particle duality of matter.  From that, the concept can be extrapolated or expanded to explain possible other, but more macro, anomalous phenomena.

Parallel Universes: Part One

Parallel universes, or alternative universes or mirror universes have had a long run of popularity in science fiction and science fantasy, in both print and visual formats. One need only look at an “Alice in Wonderland” or look no further than the “Star Trek” universe (our Universe in less than obvious disguise) to view the near endless plot variations that such parallel / alternative / mirror universes provide our heroes and heroines. Do they actually exist and do they explain anything?

There are apparently two theoretical counterparts in our real world, or in our physics. Firstly, there’s the idea that from the beginning, there’s an infinite number of parallel universes where all things that can happen, do happen. Our Universe is just one of that infinite set. In five of those universes, you 1) flip a coin – in one, it’s a heads you flip; in another, tails; in the third, the coin stands on edge! Or, in a fourth universe you decide not to flip a coin at all, or in universe #5 you decide to flip something else instead.

The other theoretical set of parallel universes is a set that ever increases, staring with just one. Universes split whenever an either/or choice is forced upon it, such that all results that can happen, happen. In this (our) Universe you decide not to flip a coin – but that decision results in a division, the universe splits and in that split, in the new universe, you do flip a coin. In that universe it comes up heads. But, that universe then splits into two and yet another universe where your flip has tails comes up. There’s also another universe where the coin lands on edge! There’s also a universe that originally splits off where you decide to flip something other than a coin. This is known as the ‘Many Worlds Interpretation’ theory, (which resulted out of a need to explain certain quantum phenomena). With every passing second, more and more universes branch off (actually trillions per second).

I’ve never been a fan of the Many Worlds Interpretation of all things quantum. That is, the universe keeps splitting each time it comes to a fork in the road. The question of where all the matter/energy comes from – created out of nothing apparently – I’ve yet to see addressed in the texts. But, many top notch scientists adopt it – perhaps as the least of all the evils certain quantum phenomena dish up. As to where they fit, all those extra universes, that’s not as much of a problem. A motel with an infinite number of rooms never has to put out a ‘no vacancy’ sign – if you get the analogy. Oh, the Many Worlds Interpretation also means that there’s no such thing as free will. You may think you have free will in deciding to wear your red dress instead of your green dress, but in the Many Worlds Interpretation, you do both – so no free will.

However, I myself go for the Copenhagen Interpretation* – when you come to a fork in the road, one and only one choice is made – the other possible choice(s) are never realized and ultimately never have any reality. But, if you start out from scratch with an infinite number of universes, or at least a vast number, then the issue of ‘where’ all the universes are is irrelevant, and the creation of all the stuff that makes them up is equally irrelevant. In the beginning, it was so!

You can have an infinite number of universes in an infinite amount of space. An analogy – there are an infinite number of whole numbers like 1, 2, 3, 4, 5, 6, etc. There’s also an infinite number of even numbers such as 2, 4, 6, 8, 10, 12, etc. Ditto an infinite number of odd numbers. Yet the infinite set of even numbers, plus the infinite number of odd numbers, equals the infinite set of whole numbers. Infinity + infinity = infinity! Or, if you like, think of your house (volume) with just one molecule (universe) in it. You’d agree there’s room for one hell of a lot more molecules (universes). If your house had infinite volume, then…

I had always assumed, and followed the assumptions of others infinitely more brilliant than I, that such theoretical constructions, such parallel / alternative / mirror universes, was forever beyond our actual reach – works of fiction aside of course. We could construct them as an intellectual exercise, but could never verify and understand the actual existence of these mental or thought experiments. That’s because these universes, if they exist, would not be part of our space-time continuum and thusly we could never interact with them.

But what if that assumption is wrong? What if parallel / alternative / mirror universes not only exist, but can and do interact with ours, and thereby give some additional credence to the adventures of our “Alice in Wonderland” and “Star Trek” characters, not to mention the reputations of those physicists who propose infinite universes or Many Worlds Interpretation theories. 

Micro & Macro Mysteries: Well, those assumptions just might now be put to the test. I’d love to be able to say I thought of this idea, even independently, it’s just that brilliant. Alas, I didn’t, and I’m kicking myself because it’s just so simple and elegant.  The credit for this goes to physicist David Deutsch, and for a fuller and better outline of his proposals, see his book cited below**. 

The basics are as follows and deals with the paradoxical and famous ‘double slit’ experiment with light – an experiment with photons.

If you shine a light (millions of photons worth) at a slit, you’ll get a blob of light on the surface behind the slit. No problems – the photon ‘bullets’ go through the slit and impact on the surface behind.

Now you shine the light (millions of photons) at two slits. Contrary to expectation, you don’t get two blobs of light – one opposite each slit – but a classic wave interference pattern of alternating light and dark areas on the surface behind. So photons aren’t ‘bullets’; light must be a wave.

Thus is demonstrated the classic wave-particle duality or paradox of light. Is light a continuous wave, or is it a collection of individual ‘bullet’ particles?

Instead of firing millions of photons at these slits at a go, redo the experiment by firing off photons one at a time – say one per hour. That can actually be done. If you fire the one per hour photons at a single slit, the picture that emerges over time is your blob of light behind the slit. Photons are behaving as ‘bullet’ particles as before.

Now, fire the photons – one per hour – at the two slits. Clearly, you’d expect two blobs of light to ultimately form on the (say photographically sensitive) surface that is behind each slit. Sometimes the single photon would go through one slit; sometimes the other. Alas, you still get a wave-like interference pattern! How can this be? What’s interfering in real time with the actual photons that you’re shooting off?

The only object capable of interfering with photons, to cause wave-like interference, an alternating light-dark pattern, is other photons. But there are no other photons in the vicinity if they are shot out at one per hour and your photon source is the only photon source!

The inescapable conclusion is that there must be other photons around that can’t be detected (seen). Call these photons virtual photons, or shadow photons or ghost photons. Where do they come from? The answer is from our parallel / alternative / mirror universes. There is therefore a form of weak interaction between universes.

How do they, parallel universe photons say, actually get here? Well, at the quantum level, all manner of virtual particles pop into and out of existence from what’s called the vacuum energy. At the extremely microscopic level, what’s often called the ‘quantum foam’, is a level seething with activity, including the popping into and out of existence of micro wormholes, wormholes that can connect one universe with another, even if only for nanoseconds. But, that’s enough to allow the transfer of micro objects, like photons, and electrons, etc. from one universe to another. It’s like seeing the ocean from space. It looks really smooth and tranquil. However, at rowboat level, there’s this twenty foot wave about to come crashing down on top of you.

To be continued…

*But with one very, very important caveat. The Copenhagen Interpretation of the quantum requires that Nature makes up Her mind when, and only when an observer or an observer’s measurement is made. Until then all is probability and nothing has reality or actual existence. The Moon has no reality unless someone is observing or measuring it! To me, observers are irrelevant – reality is reality, with or without observers. 

**Deutsch, David; The Fabric of Reality; Penguin Books, London; 1998:

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.