CERN Measured What Holds Reality Together... and It Is Only Resting

[00:00:00]On the 4th of July 2012, in a lecture hall at CERN on the border between Switzerland and France, two teams of physicists stood in front of a room that had been filling since before dawn and said that they had found it. A new particle mass somewhere between 125 and 127 billion electron volts. In the audience sat Peter Higs, 83 years old.

[00:00:25]He had written the idea down in 1964 before anyone had walked on the moon and then waited 48 years for someone to build a machine that could test it. The room applauded for a long time and it deserved to by any reasonable measure.

[00:00:40]This was one of the great days in the history of science. A guest made with a pencil confirmed by an instrument that took decades and thousands of people to assemble. And buried inside the celebration was a number nobody in that hall was toasting. Because the mass of that particle is not a piece of trivia.

[00:00:58]It is a setting. It fixes a value that governs the stability of [music] empty space itself. When theorists carried the number back to their desks and worked out what it implied, it did not land comfortably in the midst of anything. It landed on a line, almost exactly on it.

[00:01:15]Not clearly on the safe side, not clearly on the other one. Let us begin.

[00:01:22]Start with the word vacuum because everything that follows depends on getting it right. In ordinary speech, a vacuum is nothing. Pump the air out of a jar and what remains is emptiness, absence, a hole where matter used to be.

[00:01:37]That is not what a physicist means. In modern physics, the vacuum is the lowest energy state of a set of fields that fill all of space. And fields do not switch off. They settle, remove every particle, pump away every atom, absorb every photon, [music] and the fields are still there, still holding a value. The vacuum is not the absence of something.

[00:02:00]It is the resting position of everything. One of those fields is the Higs field. It is not confined to CERN.

[00:02:07]It is not stored anywhere. It is spread through every cubic cm of the universe, including the volume your body occupies.

[00:02:15]And it is holding a value right now as you hear this. That value is what gives mass to the fundamental particles. An electron is heavy because it drags against the Higs field. A photon is massless because it does not. Change the value and you change the mass of the electron. Change the mass of the electron and you change the size of every atom, the length of every chemical bond, the temperature at which water freezes, whether a star can burn at all.

[00:02:44]The number is not decoration. It is the peg the rest of it hangs on. So the obvious question, the one theorists asked long before anyone could test it, is whether that setting is the only one available. In 1980, two physicists put an answer in print. Sydney Coleman and Frank Deluchia [music] published a paper in Physical Review D Volume 21 under a title so dry it reads as camouflage.

[00:03:10]Gravitational effects on and of vacuum decay. 11 pages of mathematics about what happens if the vacuum we live in is not the lowest one available, but merely a low one, a ledge partway down the mountain rather than the valley floor.

[00:03:26]And near the end, having finished the calculation, Coleman and Deluchia stopped writing like mathematicians.

[00:03:33]They wrote [music] this instead. Vacuum decay is the ultimate ecological catastrophe. In the new vacuum, there are new constants of nature. After vacuum decay, not only is life as we know it impossible, so is chemistry as we know it. Notice what they did not say. They did not say everything would be destroyed. They said the constants would be different and that chemistry itself would not survive the change. Not the buildings, not the [music] planet.

[00:04:01]Chemistry, the rules by which atoms are permitted to hold on to one another.

[00:04:06]Coleman then removed the last consolation available, [music] the thought that some other kind of structure might one day arise in the new vacuum and find its own way to something like joy. He wrote that this possibility had now been eliminated. Here is the mechanism they were describing. If our vacuum sits on a ledge, then somewhere in the space of possible values, there is a lower one. The field is separated from it by a barrier. Classically, that is the end of the story. Not enough energy, [music] no crossing. Quantum mechanically, it is not the end of the story at all. Given enough time, a small region of space somewhere in the universe can tunnel straight through the barrier and settle into the lower value.

[00:04:49]It does not need a cause. It does not need to be triggered. It simply becomes at some random moment in some random place a bubble of the true vacuum sitting inside the false one. And because the inside of that bubble is at lower energy than the outside, it grows.

[00:05:07]The energy difference goes into pushing the wall outward. The wall accelerates and it keeps accelerating [music] until it is moving at very nearly the speed of light. That last detail is the one worth sitting with. It is the only place in this story where the physics offers nothing at all. A wall traveling at the speed of light arrives at the same instant as the light that would have shown it to you. There is no glow on the horizon, no warning shot, no 30 seconds to work out what is happening.

[00:05:37]The first moment you could possibly detect it is the moment it is already here. And by then [music] the constants have changed and there is nothing left with the structure required to notice.

[00:05:47]For 32 years that stayed a curiosity because the calculation had a hole in it. Whether our vacuum sits on a ledge or on the valley floor depends on two numbers. And in 1980 nobody had either.

[00:06:02]One is the mass of the Higs Bzon. The other is the mass of the top quark, the heaviest particle in the standard model and the one that couples to the Higs field more strongly than anything else.

[00:06:13]Those two numbers between them [music] decide the shape of the landscape the field is sitting in. Get both and the [music] question stops being philosophy.

[00:06:23]The second number came first. Firmmy lab found the top quark in 1995.

[00:06:29]Its mass has been measured and rememeasured ever since. And the value that matters for this particular calculation sits close to 172.4 billion electron volts with an uncertainty of about 0.7.

[00:06:43]Then came the 4th of July 2012 and the other number. The best current measurements put the Higs Bzon near 125.1 billion electron volts and the uncertainty is roughly 1/10enth of one.

[00:06:59]two numbers, both finally [music] in hand, the calculation could be run. The answer was not the one anybody would have chosen. With those two masses, the mathematics that describes the Higs field does something peculiar as you follow it upward to higher and higher energies. The term that keeps the field stable weakens. Then it crosses zero.

[00:07:21]Then it goes negative somewhere in the region of 10 11th billion electron volts. Beyond that point, the equations stop saying our vacuum is the bottom.

[00:07:31]They say there is somewhere lower to go.

[00:07:34]It is worth understanding how remote that scale is. The Large Hadron Collider, the most powerful machine of its kind [music] ever built, collides protons at around 14,000 billion electron volts. The energy where the equations turn over, is [music] roughly 10 million times higher than that. No experiment on Earth will reach it. No experiment being designed will reach it.

[00:07:59]We are not looking at this directly and we never have been. We are extrapolating a formula from where we can measure it into a region where nobody can check [music] and then reading off what it says about the ground we are standing on. Now read the size of the number, not just the [music] sign. It does not plunge. It dips below zero by a whisker and stays [music] there. That is the difference between a universe that is unstable and a universe that is metastable.

[00:08:27]Unstable means falling. Metastable means resting somewhere that is not the lowest point available [music] and staying there potentially for an almost unimaginable length of time. The estimates for how long our vacuum should survive run to numbers with more zeros in them than there are atoms in your body. On any time scale a human being can hold in mind, nothing is going to happen. Which sounds like relief. It is not quite because of how close it is.

[00:08:58]Shift the measured mass of the top quark downward by a fraction under two standard deviations, well inside the range current experiments cannot rule out, and the negative dip [music] disappears entirely. The vacuum becomes absolutely stable, permanent. A universe with no lower rung to fall to. That is the actual state of the evidence. The calculation that says our universe is temporary and the calculation that says it is eternal are separated by less than two sigma on a single measurement.

[00:09:31]Physicists have written down exactly what it would take to settle it too. Cut the uncertainty on the top quark mass and on one other constant by a factor of two or three. Then the question resolves at the five sigma standard that particle physics treats as proof.

[00:09:50]We have not done it. The measurement is not there yet. Part of the reason is that the top quark is unusually difficult to pin down. It is the heaviest particle known and it is so heavy that it falls apart almost immediately after it is created in less time than it takes to bind with anything else. Nothing ever gets to hold one still and weigh it. Every measurement is a reconstruction assembled backward out of the debris of its decay. And the number that comes out depends in part on the theoretical model used to do the assembling. Different methods give slightly different answers. The gap between them is small. It is also at the moment the width of the question. And there is one more thing the mathematics permits which follows from the fact that nucleation is random and the universe is very large. A bubble does not have to begin here. It could have begun anywhere at any time in the last 13 billion years in any of the countless regions of space too far away for their light to have reached us yet. If one did, it is coming. And it has been coming for longer than the Earth has existed. And there is no observation anyone could make that would tell us. The theory does not say this has happened. [music] It says nothing rules it out. So the most fundamental question available whether the universe we live in is a permanent thing or a temporary one currently sits inside the error bars of a number that much is arithmetic [music] and arithmetic can be checked. What comes next cannot be settled that way because the people who do this work for a living have looked at the same calculation [music] with the same two numbers in front of them and come to conclusions so far apart that they cannot all be describing the same universe.

[00:11:32]On the night of the 15th of October 1991, in the desert west of Salt Lake City, an instrument called the FL's eye was watching the air above Dougway proving ground. It was not a telescope.

[00:11:45]It was a field of mirrors aimed at nothing in particular, waiting for the faint blue glow that appears when something arrives from space and hits the top of the atmosphere hard enough to make it flues.

[00:11:57]Most nights it caught the ordinary traffic of the galaxy. That night, it caught a flash so far outside the catalog that the team went back through the calibration looking for the mistake.

[00:12:07]There was no mistake. A single particle, almost certainly one proton, had come in carrying 320 billion billion electron volts. It helps to translate that one proton, an object with no size worth speaking of, arrived with roughly the kinetic energy of a baseball thrown at [music] 60 mph. Not a beam of them, one.

[00:12:31]The physicists [music] who found it gave it a name that has survived in the literature ever since, which tells you something about how the discovery felt.

[00:12:39]They called it [music] the Oh My God particle. Nothing has been recorded above it in the 35 years since. Though in 2021, a detector in the same stretch of Utah caught one nearly as violent.

[00:12:51]Neither arrival direction points back at anything in the sky that looks capable of producing them. This matters here for a reason that has nothing to do with mystery. The universe has been running collisions like that one everywhere for 13 billion years. Whatever we can do at CERN, nature did first, harder, and at a scale no budget could buy. So hold that thought and put the obvious question to the calculation from the last chapter.

[00:13:18]If the vacuum really is sitting on a ledge and a bubble of the true vacuum can appear at any moment without a cause, then why has it not appeared already?

[00:13:28]13.8 billion years is a long time. The observable universe is a large place.

[00:13:34]The theory says nucleation is random, which means it has had every opportunity across an enormous volume for the whole history of everything. And here we are.

[00:13:45]That objection is sound. And the answer to it is arithmetic. The rate is low. A direct calculation inside the standard model puts a floor under the lifetime of our vacuum state [music] at greater than 10 to the 65th years at 95% confidence.

[00:14:01][music] Set that against the age of the universe and the ratio is not close. On any time scale that means anything to a person or a species [music] or a star, the honest expectation is that nothing happens. But there is a property of this process that does not behave the way intuition insists it should. Quantum [music] tunneling has no memory. The chance that a bubble forms in a given volume of space in the next second is the same as it was a billion years ago and the same as it will be a billion years from now.

[00:14:34]The vacuum is not aging. It is not becoming due. It is also not earning safety by having lasted. Every second is an independent draw from the same distribution. And the draws that came before tell you only that the odds are long. They do not tell you that this one is [music] safe. Survival is evidence about the rate. It is not a promise about the next moment. Which brings up the fear that actually gets asked, [music] the one that put the word CERN into headlines twice in 20 years. If a violent enough event could knock the field over the barrier, could we do it ourselves?

[00:15:11]We are after all in the business of building machines whose entire purpose is [music] to concentrate energy into the smallest possible space. The Large Hadron Collider is the most extreme such machine ever assembled. The worry has a shape to it that sounds reasonable. The answer starts by taking apart the question. In 2000, four physicists at MIT, [music] Yale, and the Institute for Advanced Study wrote a formal review of exactly this class of concern. And their first move was to separate [music] two things people run together. Total energy is not energy density. What decides whether a collision can reach into new physics [music] is not how much energy is present, but how tightly it is packed. As they put it, [music] if total energy were a measure, then a batter striking a major league fast ball would be performing a far more dangerous experiment than any contemplated at a high energy accelerator.

[00:16:11]Now, go back to the particle over Utah.

[00:16:13]It carried the energy of a thrown baseball, but it spent that energy hitting a stationary nucleus. And most of the energy in a fixed target collision goes into simply carrying the wreckage forward rather than into the collision itself. Account for that properly and the encounter still lands at a few thousand trillion electron volcy of collision energy. The Large Hadron Collider reaches 14,000 [music] billion. The Particle Over Utah beat the best machine we have ever built by a factor of a couple of hundred and it did it without being asked.

[00:16:48]That comparison is not a curiosity. It is the safety argument and it was made before most of these machines existed.

[00:16:56]In 1983, Piet Hut and Martin Ree published a short paper in Nature under a title that asked the question plainly, "How stable is our vacuum?" Their reasoning was simple enough to state in a sentence, "A vacuum transition once [music] it starts spreads outward at the speed of light and consumes everything it reaches." So, if one had ever begun anywhere inside the region of space whose light has had time to arrive here, we would not be having this conversation.

[00:17:25]Then they [music] counted. They worked out how many high energy collisions have already taken place inside our past light cone using measured cosmic ray fluxes. And the number is roughly [music] 10 to the 47th.

[00:17:38]And here is the part that lands. They found that proton on proton collisions at a collision energy above 10^ the 11th billion electron volts have occurred so often in the volume and the span of time whose outcome we can personally vouch for [music] that even collisions that extreme can be treated as demonstrated safe.

[00:17:58]Look at that energy again. 10^ the 11th billion electron volts [music] is where the equations from the last chapter turn over. It is the scale we said no experiment on Earth would ever reach.

[00:18:10]the region we can only extrapolate into.

[00:18:13]Nature has been running the experiment there for 13 billion years at a rate we can measure in a volume we can define.

[00:18:21]The result is not a theory. The result is that you are here to hear this. That evidence has held up. A recent analysis of what it would actually take to trigger the Higsfield over the barrier found that the process is exponentially suppressed and that the odds of provoking a decay in a collision come out comparable to the odds of it happening spontaneously anyway. There is no shortcut, no resonance to exploit.

[00:18:48]The machines in Geneva and Long Island are not a threat to the vacuum. And the people who study this most closely are the ones who establish that most firmly.

[00:18:57]The kaleidophhere is the one part of this story that is genuinely [music] settled.

[00:19:02]Third hope and the most sophisticated of them, gravity.

[00:19:07]Coleman and Deluchia were writing about a quantum field and quantum field theory and general relativity are famously bad company. Surely the calculation is missing the one force that shapes everything at large scale. And surely putting it back in changes the answer.

[00:19:23]It does change the answer. And this is the place where the story briefly turns in our favor. Look again at the title of the 1980 paper, gravitational effects on and of vacuum decay. Gravity was not left out. It was the [music] subject.

[00:19:40]And what Coleman and Deluchia found is that including it generally makes decay less likely, not more. A bubble has to reach a critical size before its interior can pay for its own wall.

[00:19:52]Gravity distorts the geometry inside the bubble in a way that makes that harder to achieve. Push it far enough and the effect becomes absolute. In the limiting case, where the energy difference between the false vacuum and the true one is small enough, gravity does not merely slow the process down. It stabilizes the false vacuum completely and the decay cannot happen at all. That is a real result and it is [music] the strongest piece of good news in this entire subject.

[00:20:23]Then in 2013, three physicists at Durham and Newcastle asked what happens if space is not smooth. The Coleman and Deluchia calculation assumes a uniform background. The actual universe is not uniform. It is full of objects that bend spaceime severely and the most severe of them are black holes. Ruth Gregory, Ian Moss, and Benjamin Withers worked out what a bubble does when there is a black hole sitting where it forms. and found that the black hole does not resist the process, [music] it hosts it. In their words, the inhomogeneity significantly enhances the nucleation rate and the black hole acts as a nucleation site for the bubble. They also noted that the effect is larger than previously believed. So, gravity gives with one hand. The smooth calculation is more stable than the one without gravity in it. And gravity takes with [music] the other because the universe is not smooth and it contains an estimated 100 million black holes in our galaxy alone. Each one a place where the barrier is easier to cross than the textbook version says.

[00:21:28]Gravity [music] was supposed to be the reassurance. It turned out to be a second question, which leaves the last hope, and it is the one most working physicists actually hold. The standard model is not finished. We know it is not finished [music] because it has nothing to say about dark matter or the mass of the neutrino or why there is more matter than antimatter. So, the instability may simply be an artifact of running an incomplete theory 10 million times past the last energy anyone [music] has tested it at. New physics appears somewhere along the way. The curve never turns over and the problem dissolves.

[00:22:04]John Ellis of King's College London and CERN has made that case about as clearly as it can be made. The universe, he has written, is metastable with an estimated lifetime before it decays that is many, many orders of magnitude longer than its age. And on what should be done about the turnover, [music] his position is that some physics beyond the standard model must appear below the turndown scale [music] and stabilize the vacuum that we live in. Read that second sentence carefully because of what kind of statement it is. [music] It is not a measurement. It is a requirement being placed on nature by the fact that we are here. The argument runs backward from the conclusion we want to [music] the physics that would deliver it. And it is perfectly respectable reasoning and it has been right before. But notice the price. To be reassured by it, you have to accept that the theory generating the frightening answer is the wrong theory.

[00:22:57]In a regime where we have no data and [music] no prospect of any. The comfort and the admission are the same sentence and every one of these answers has that shape. The vacuum has lasted but lasting buys nothing. We cannot trigger it which is true and settled and also says nothing about whether it happens on its own. Gravity helps until you put a black hole in the calculation. New physics might save us, provided the physics we have is wrong in the specific way we need it to be. What is left when the easy answers have been used up is a calculation that nobody can check and a line the measurement sits almost exactly on top of. At that point, the question stops being what the mathematics says.

[00:23:41]It becomes what the people who understand the mathematics believe it means. And in October of 2025, somebody finally did the obvious thing [music] and asked them.

[00:23:52]In October of 2025, an email went out to 105 people. It was not an [music] announcement and it did not come from a laboratory. It was a questionnaire assembled by four researchers working out of Imperial College London, the University of Cairo, and a research lab in California. and the recipients had been selected by a single criterion.

[00:24:16]Each of them had published peer-reviewed work on the decay of the vacuum. These were not commentators. They were the people who had actually done the mathematics. And the survey asked them in plain language what they personally believed the mathematics meant. [music] 20 of them answered from 17 different institutions.

[00:24:36]That is a small number in absolute terms and a large one in context [music] because the population of physicists who work seriously on this problem is not much bigger than the room it would take to seat them. The central question was as direct as it could be made. What is your credence as a percentage that our vacuum is metastable?

[00:24:56]Not what does the standard model predict. What do you think is true? The average came back at 45.6%.

[00:25:04]Read quickly. That looks like the tidiest possible result. Just under half. A coin balanced on its edge. The field in careful equilibrium. Nobody overcommitting in either direction. It is the kind of number that invites a summary sentence about how physicists are evenly split on whether the universe is temporary.

[00:25:26]That sentence would be wrong because the survey also reported the spread around that average and the spread was 33.7 percentage points. When the deviation is nearly as large as the mean itself, the mean has stopped describing anybody.

[00:25:42]Somewhere in that data, there is not a cluster of people hovering near half.

[00:25:47]There is something else. There is. When the individual answers are laid out, they fall into three separate groups with gaps between them. Seven of the 20 put their credence between 70 and 95%.

[00:26:02]They think our vacuum is very probably metastable.

[00:26:06]Seven others put it between 0 and 10%.

[00:26:09]They think it very probably is not. The remaining six sat at roughly 50%. Which in this context is not a position but a refusal to take one. two camps of equal size facing opposite directions and a third group declining to referee.

[00:26:27]That shape is worth pausing on because it is not what uncertainty normally looks like.

[00:26:33]Ordinary scientific uncertainty is a hump. People cluster around a best estimate and trail off on either side and the average sits in the middle and means something. This is not a hump. It is two peaks with a valley between them.

[00:26:49]The average of 45.6 is a number that almost none of the respondents actually hold. It is an artifact of averaging a disagreement.

[00:26:59]The authors did not soften it. In their abstract they record substantial disagreement among respondents and in the body they write that the debate surrounding vacuum stability does not stem from a single source but from a complex mix of experimental, theoretical and even philosophical factors.

[00:27:19]Now hold that against something that ought to be strange.

[00:27:22]Every one of these people is looking at the same Higs mass, the same top quark mass, the same potential, the same equations, the same published stability calculations running on the same measurements from the same two detectors.

[00:27:38]There is no hidden data. Nobody in the low camp has a number the high camp lacks. They are disagreeing about a shared object.

[00:27:47]What separates them is what they think the equations are for. The survey found broad agreement on one point, which is that present-day particle physics does predict metastability.

[00:27:59]That is not really in dispute. What is in dispute is whether present-day particle physics should be believed out there. The authors put it precisely.

[00:28:09]The division indicates that while many experts agree that metastability is predicted by present-day particle physics, there is a clear recognition of the standard model's limitations.

[00:28:20]So the low camp is not disputing the arithmetic from chapter 1. They are saying the arithmetic is being run 10 million times past the last place anyone has checked it and that the answer it produces is a statement about the model rather than about the universe.

[00:28:36]The high camp is saying that this is the best theory we have ever had, that it has survived every test we could throw at it, and that declining to believe its output in the one regime we cannot test is not caution, but wishful thinking.

[00:28:51]Both positions are defensible. That is the problem. Neither group can perform the experiment that would embarrass the other.

[00:29:00]The survey asked a second question, and the answers to it split the same way. If our vacuum is metastable, what is the chance that a sufficiently advanced technology could deliberately trigger the decay? The average came back at 18.8% with a spread of 42. A spread larger than twice the mean is not a measurement of anything. It is a picture of a room with no shared view. Look at what produced it. 11 of the 20, a clear majority, answered zero. Not low, zero.

[00:29:35]In their judgment, the thing is simply not doable by anyone ever. And chapter 2 is the reason why. If cosmic rays operating at the turnover scale across our entire past light cone could not manage it, no machine is going to. The remaining nine dragged the average up almost single-handedly.

[00:29:55]Same experts, same paper, same question.

[00:29:58]And the answers occupy opposite ends of the available range.

[00:30:02]Even the ones who allowed the possibility were careful about it. The authors record that among respondents who considered vacuum decay theoretically possible. It was generally expected that artificial induction would pose significant technological challenges even for a civilization with galactic resources.

[00:30:21]That is not a warning. It is the most heavily qualified maybe in the literature. And it is worth stating plainly because this is the exact point where this subject usually stops being physics. Nobody is going to do this.

[00:30:35]That much the room agrees on which raises the practical question. If the experts cannot settle it by argument, what would settle it by measurement?

[00:30:45]There is a precise answer and it was updated as recently as March of this year. Good hiller, Tim Her, Daniel Litim and Tom Stritner have been revisiting the stability calculation using the highest available orders in pertubation theory and their conclusion is not philosophical at all. The stability of the electroeak vacuum they write centrally depends on the values of the top mass and the strong coupling constant. Then they cost it out.

[00:31:15]Reducing the uncertainties on those two quantities by a factor of two to three they estimate is sufficient to establish or refute standard model vacuum stability at the five sigma level. That is the threshold particle physics treats as discovery. It is not a fantasy target and it does not require a new universe of technology.

[00:31:37]It requires better numbers on two constants we already measure. The obstacle is which two? The strong coupling constant is difficult. The top quark mass is worse and chapter 1 explained why. It is the heaviest particle we know of. It disintegrates before it can bind to anything. [music] And every value we have is reconstructed backward out of decay products using a theoretical model to do the reconstruction.

[00:32:04]Different methods disagree slightly and that residual disagreement is not noise around the answer. At the moment, it is the width of the question. So the resolution is real. It is specified. It is achievable and it is not scheduled.

[00:32:20]And underneath even that something does not go away. Suppose the measurement arrives and the uncertainty closes and the calculation returns a clean five sigma verdict. [music] It would still be a verdict delivered by the standard model about a region of energy 10 million times beyond anything the standard model has been tested at. The low camp's objection survives the better measurement completely intact.

[00:32:45]This is why the survey found that resolving these questions primarily depends on developing theories that go beyond the standard model of particle physics. The precision fight and the theory fight are different fights and winning the first one does not end the second which leaves us more or less where the room is. Two numbers measured well enough to raise the question and not well enough to close it. A calculation everyone can reproduce and nobody can check. A line that our universe sits on almost exactly with the safe side and the temporary side separated by less than two standard deviations on a single quantity.

[00:33:28]And 20 people who have spent their careers on this split seven against seven with six abstaining.

[00:33:35]None of this changes anything about tomorrow. Whatever the truth turns out to be, the predicted survival time of our vacuum runs past the age of the universe by a margin so enormous that no human decision could ever be affected by it. Nothing about this is urgent, and any version of this story that suggests otherwise is selling something.

[00:33:55]The strangeness here is not danger. It is that the most basic property of the place we live, whether it is permanent or provisional, is currently an open question among the few people qualified to have an opinion, and they have arrived at opposite answers from identical evidence.

[00:34:12]Sydney Coleman saw where that ends, having worked out what a transition would do to the constants of nature, he wrote that after vacuum decay, not only is life as we know it impossible, [music] so is chemistry as we know it.

[00:34:26]Then he removed the last comfort on offer, the idea that something in the new vacuum might eventually arise and find its own way to something like joy, and noted that this possibility had now been eliminated.

[00:34:38]He was not writing to frighten anyone.

[00:34:41]He was following the mathematics to the place it went, and if it ever happens, it will not be observed. The wall travels at very nearly the speed of light, which means it arrives at the same instant as the light that would have announced it.

[00:34:55]No glow on the horizon, no warning, no interval in which to understand, not a catastrophe anyone experiences [music] because experience requires structure and the structure does not survive the change. Just a different set of constants [music] expanding outward at the speed of light through a universe that was never told.

[00:35:15]The honest ending is that we do not know and the people best equipped to know do not agree. [music] Our vacuum has held for 13.8 8 billion years and the odds say it will hold for very much longer than that. But it is sitting on a line. The measurement is not yet sharp enough to say which side.

[00:35:34]And the calculation that would tell us is running far past where anyone has ever checked.

[00:35:39]That is the actual state of human knowledge about whether the universe is a permanent thing. A number, an error bar, and a room full of experts who cannot agree on what it means.