Uncommon Descent Saturday contest: What would be acceptable evidence for other universes?

the infinite number of parallel universes was only conjectured in response to the absolutely incredible level of fine-tuning in the universe

Actually I believe the Many Worlds Hypothesis dates from the 50s-60s and was in response to quantum mechanics, not fine-tuning. As many posters have alluded to, what constitutes evidence for a multiverse theory is going to depend on the specific formulation of that theory. If the theory defines universes as completely non-interacting, then there can be no direct evidence. If the theory predicts some method of interaction, say the "bumping" of near universes described above, then there may be evidence. Without an actual, concrete, theory that fully defines "universe", we can't say what evidence for that theory could look like. MikeThicke

Evidence that other universes exist seems incoherent. The recent debate between Lawrence Krauss and William Lane Craig saw Krauss, a physicist, admit that other universes cannot communicate with us or exert any forces on us. He went on to say, however, that such a postulation could enter the realm of physics inquiry if there were other theories that explained the four forces of nature, but that currently there are none, and he didn't seem to assume any confidence that any will be forthcoming, excited though he was at the mere thought. As he spoke, he implied that even if physicists had a solid theory to explain and whereby the forces of nature could be understood, that even then it would take a leap of strained conjecture to show that there is any evidence for the existence of other universes. But, Dr. Krauss' statements themselves don't show the incoherence of the idea of evidence for other universes. They merely show that even those who most want to prove that other universes are likely, or even possible, don't really hold out any hope that they will, or can, ever have evidence for them. The "can" is where the incoherence comes in. First off, if there are other universes, how would they be distinct from our own? Would they be within our universe? If so, they would surely only be considered a new phenomena within, and therefore a part of, our own universe. Take for example the ideas of dark energy or dark matter. These forces are not assumed to be evidence of other universes within our universe, even though they are something other than what we previously knew within our universe. Why? Simply because they are within our universe. And, needless to say, if another universe within our universe was just like our own universe . . . well, like I said, needless to say. Or, would other possible universes be outside our universe? If so, how could we ever hope to know of them? If physics breaks down at the edge of our universe, which must be the case since scientists admit that physics do break down at what is called the singularity, then whatever "space" or span there is between any other universe and our own would be like the proverbial brick wall. It would not allow scientific inquiry to proceed any further. Indeed, the very idea of a physical span outside of our universe isn't even imaginable, for when we leave our universe we leave everything we know. Even if there was "something" outside our universe, we could only conclude that it was nothing, for if it was something like our own universe, we would consider it to be our own universe and think we hadn't gone far enough to break out of our own universe. Perhaps, then, other possible universes would be evidenced through exerting forces that are detectable within our universe (despite Dr. Krauss saying that isn't possible). But this would go back to the first point above. If we detected forces from other universes within our own universe, we would conclude that this is only a feature of our own universe previously unknown to us. Very recently, Roger Penrose and Vahe Gurzadyan found what they called evidence for other universes by a "bruising" effect within our own universe. It was quickly pointed out, however, that the effects that were noticed, in our own universe of course, were simply a characteristic of our own universe. What we find in our own universe can only be considered to be a feature of our own universe. If the forces were of another universe within our universe, it would be considered a part of our universe. If the forces were from outside our universe, since we cannot even rationally imagine what lies outside the border of our own universe, we would have no way of determining that what was being observed was from anything outside our own universe. If we have no knowledge of what may lie beyond our universe, how could we know what effects it could or should have on us? Therefore we are forced to conclude that any proposed effects from outside our universe are really only a feature of our present universe. I think this is a fair philosophical case to show the incoherence of thinking we can actually have evidence for other universes, but since the question raised is to show what such evidence might be, I luckily have an answer, and a somewhat "scientific" one at that! "Science" isn't always about science. It is, in some cases, about philosophical and metaphysical presuppositions. When data does not adhere to some cherished notions, either the notions or data have to go. Sadly, the data meets the circle file more frequently in some cases than do the notions. Now, the circle file of scientific data is a very sophisticated file, for all things scientific are very sophisticated these days. Normal people have trash bins made of metal, plastic, or some sort of rubber. They are lined with plastic bags and are often twist-tied before going to the curb. But science's data trash bins are made of things like ad hoc, are lined with ad hominems, and are twist-tied with equivocations. Therefore, I say, redefining our own universe will be the first step in finding "evidence" for other universes, making any subsequent steps like a walk in the park---or is that another universe? This isn't real evidence, mind you, but something that many will claim, in spite of the stench, is evidence nonetheless. Brent

If there are other universes the only possible kind of evidence would be their effects. There is a theory called "eternal inflation" put forward by Steven Feeny, which states that we are actually one of many "bubble universes" in a vast cosmos. At times, these bubbles bumped into eachother. Feeny says there is evidence of these "bruises" in the CMB, but it's tentative. Data from the Planck spacecraft should bring higher resolution and might settle the matter. anaruiz

Oddly enough, of the 1,000,000,000,000+ universes that border ours, one of them is exactly like ours, except it is 7 days earlier and I hadn't yet obtained a copy of The Nature of Nature. After travelling there in my Delorian, I observed that I did not win the contest. Therefore, me not winning the contest is proof that at least that universe exists in addition to this one. And for two universes that are exactly seven days apart and in which I have/don't have The Nature of Nature, to exist, obviously there must be an infinite number of others. (Actually, I've been to many others and have kept 7 of them that were small enough to fit in the trunk of my Delorian...but you'll just have to take that by faith). I was rather bummed in that other universe after learning of my loss, but I won't be in this universe because I've already got a copy of The Nature of Nature. rpvicars

What would be acceptable evidence for other universes?

If I could murder Andrei Linde, kill Martin Rees' dog and eat it, and no one got upset about it because hey, it was bound to happen in some universe and apparently it just happened to be this one, and what they heck, in some other universe they are all still just fine. That might just be enough evidence to satisfy me. Mung

What would be acceptable evidence for other universes? The answer is rather simple- the need for a multiverse system. IOW when you have run out of probabilistic resources in the known universe, ie the resources required to explain your position, you add more resources. And once that happens then other verses just seem to fall out of the mathematics and rational thought. Joseph

EvilSnack:

I suppose that going into a wardrobe to hide, and finding oneself in a wintry glade with a lampost, would be excellent evidence of alternate universes.

That could still be a place in this universe. It's a pretty big place, ya know. Joseph

Since the atheists do not have ANY evidence whatsoever for a infinite number of parallel universes, and indeed the infinite number of parallel universes was only conjectured in response to the absolutely incredible level of fine-tuning in the universe (as opposed to their other materialistic dodge, of infinite parallel universes, for explaining the cause of quantum wave collapse in the 1950's), should not the atheists at least be forced to provide any scientific reason whatsoever other than their irrational distaste for Theism as for why this extravagant conjecture or theirs was made in the first place? ,,,And despite the atheists stunning lack of evidence for their 'desired' answer of a infinite number of parallel universes, to explain the extreme fine tuning of this universe, Theists actually do have tangible 'real' evidence of a 'highest transcendent realm' which created this universe. notes; Quantum Teleportation - IBM Research Page Excerpt: "it would destroy the original (photon) in the process,," http://www.research.ibm.com/quantuminfo/teleportation/ ,,,Verification of Conservation of Quantum Information Quantum no-hiding theorem experimentally confirmed for first time Excerpt: In the classical world, information can be copied and deleted at will. In the quantum world, however, the conservation of quantum information means that information cannot be created nor destroyed. This concept stems from two fundamental theorems of quantum mechanics: the no-cloning theorem and the no-deleting theorem. A third and related theorem, called the no-hiding theorem, addresses information loss in the quantum world. According to the no-hiding theorem, if information is missing from one system (which may happen when the system interacts with the environment), then the information is simply residing somewhere else in the Universe; in other words, the missing information cannot be hidden in the correlations between a system and its environment. http://www.physorg.com/news/2011-03-quantum-no-hiding-theorem-experimentally.html Further reflection on the quantum teleportation experiment: That a photon would actually be destroyed upon the teleportation (separation) of its 'infinite' information to another photon is a direct controlled violation of the first law of thermodynamics. (i.e. a photon 'disappeared' from the 'material' universe when the entire information content of a photon was 'transcendently displaced' from the material universe by the experiment, when photon “c” transcendently became transmitted photon “a”). Thus, Quantum teleportation is direct empirical validation for the primary tenet of the Law of Conservation of Information (i.e. 'transcendent' information cannot be created or destroyed). This conclusion is warranted because information exercises direct dominion of energy, telling energy exactly what to be and do in the experiment. Thus, this experiment provides a direct line of logic that transcendent information cannot be created or destroyed and, in information demonstrating transcendence, and dominion, of space-time and matter-energy, becomes the only known entity that can satisfactorily explain where all energy came from as far as the origination of the universe is concerned. That is transcendent information is the only known entity which can explain where all the energy came from in the Big Bang without leaving the bounds of empirical science as the postulated multiverse does. Clearly anything that exercises dominion of the fundamental entity of this physical universe, a photon of energy, as transcendent information does in teleportation, must of necessity possess the same, as well as greater, qualities as energy does possess in the first law of thermodynamics (i.e. Energy cannot be created or destroyed by any known material means according to the first law). To reiterate, since information exercises dominion of energy in quantum teleportation then all information that can exist, for all past, present and future events of energy, already must exist. Reflections on the 'infinite transcendent information' framework and the 'eternal and temporal' frameworks: The weight of mass becomes infinite at the speed of light, thus mass will never go the speed of light. As well, mass would disappear from our sight if it could go the speed of light, because, from our non-speed of light perspective, distance in direction of travel will shrink to zero for the mass going the speed of light, whereas conversely, if mass could travel at the speed of light its size will stay the same while all other frames of reference not traveling the speed of light will disappear from its sight. As well time, as we understand it, would come to a stop at the speed of light. To grasp the whole 'time stopping at the speed of light' concept more easily, imagine moving away from the face of a clock at the speed of light. Would not the hands on the clock stay stationary as you moved away from the face of the clock at the speed of light? Special Relativity - Time Dilation and Length Contraction - video http://www.youtube.com/watch?v=VSRIyDfo_mY For us to hypothetically travel at the speed of light, in this universe, only gets us to first base as far as quantum entanglement, or teleportation, are concerned. That is to say, traveling at the speed of light only gets us to the place where time, as we understand it, comes to complete stop for light, i.e. gets us to the eternal, 'past and future folding into now', framework of time. This higher dimension 'eternal' inference for the time framework of light is warranted because light is not 'frozen within time' yet it is shown that time, as we understand it, does not pass for light. "I've just developed a new theory of eternity." Albert Einstein - The Einstein Factor - Reader's Digest "The laws of relativity have changed timeless existence from a theological claim to a physical reality. Light, you see, is outside of time, a fact of nature proven in thousands of experiments at hundreds of universities. I don’t pretend to know how tomorrow can exist simultaneously with today and yesterday. But at the speed of light they actually and rigorously do. Time does not pass." Richard Swenson - More Than Meets The Eye, Chpt. 12 Light and Quantum Entanglement Reflect Some Characteristics Of God - video http://www.metacafe.com/watch/4102182 It is very interesting to note that this strange higher dimensional, eternal, framework for time, found in special relativity, finds corroboration in Near Death Experience testimonies: 'In the 'spirit world,,, instantly, there was no sense of time. See, everything on earth is related to time. You got up this morning, you are going to go to bed tonight. Something is new, it will get old. Something is born, it's going to die. Everything on the physical plane is relative to time, but everything in the spiritual plane is relative to eternity. Instantly I was in total consciousness and awareness of eternity, and you and I as we live in this earth cannot even comprehend it, because everything that we have here is filled within the veil of the temporal life. In the spirit life that is more real than anything else and it is awesome. Eternity as a concept is awesome. There is no such thing as time. I knew that whatever happened was going to go on and on.' Mickey Robinson - Near Death Experience testimony 'When you die, you enter eternity. It feels like you were always there, and you will always be there. You realize that existence on Earth is only just a brief instant.' Dr. Ken Ring - has extensively studied Near Death Experiences It is also very interesting to point out that the 'light at the end of the tunnel', reported in many Near Death Experiences(NDEs), is also corroborated by Special Relativity when considering the optical effects for traveling at the speed of light. Please compare the similarity of the optical effect, noted at the 3:22 minute mark of the following video, when the 3-Dimensional world 'folds and collapses' into a tunnel shape around the direction of travel as an observer moves towards the 'higher dimension' of the speed of light, with the 'light at the end of the tunnel' reported in very many Near Death Experiences: Traveling At The Speed Of Light - Optical Effects - video http://www.metacafe.com/watch/5733303/ Near Death Experience – The Tunnel, The Light, The Life Review – view http://www.metacafe.com/watch/4200200/ The NDE and the Tunnel - Kevin Williams' research conclusions Excerpt: I started to move toward the light. The way I moved, the physics, was completely different than it is here on Earth. It was something I had never felt before and never felt since. It was a whole different sensation of motion. I obviously wasn't walking or skipping or crawling. I was not floating. I was flowing. I was flowing toward the light. I was accelerating and I knew I was accelerating, but then again, I didn't really feel the acceleration. I just knew I was accelerating toward the light. Again, the physics was different - the physics of motion of time, space, travel. It was completely different in that tunnel, than it is here on Earth. I came out into the light and when I came out into the light, I realized that I was in heaven.(Barbara Springer) Also, hypothetically traveling at the speed of light in this universe would be instantaneous travel for the person going at the speed of light. This is because time does not pass for them, but, and this is a big but; this 'timeless' travel is still not instantaneous and transcendent to our temporal framework of time, i.e. Speed of light travel, to our temporal frame of reference, is still not completely transcendent of our framework since light appears to take time to travel from our perspective. In information teleportation though the 'time not passing', eternal, framework is not only achieved in the speed of light framework/dimension, but also in our temporal framework. That is to say, the instantaneous teleportation/travel of information is instantaneous to both the temporal and speed of light frameworks, not just the speed of light framework. Information teleportation/travel is not limited by time, nor space, in any way, shape or form, in any frame of reference, as light is seemingly limited to us. Thus 'pure transcendent information' is shown to be timeless (eternal) and completely transcendent of all material frameworks. Moreover, concluding from all lines of evidence we have now examined; transcendent, eternal, infinite information is indeed real and the framework in which 'It' resides is the primary reality (highest dimension) that can exist, (in so far as our limited perception of a primary reality, highest dimension, can be discerned). "An illusion can never go faster than the speed limit of reality" Akiane - Child Prodigy - Music video http://www.metacafe.com/watch/4204586 Logic also dictates 'a decision' must have been made, by the 'transcendent, eternal, infinite information' from the primary timeless (eternal) reality 'It' inhabits, in order to purposely create a temporal reality with highly specified, irreducible complex, parameters from a infinite set of possibilities in the proper sequential order. Thus this infinite transcendent information, which is the primary reality of our reality, is shown to be alive by yet another line of evidence besides the necessity for a ‘first mover’ to explain quantum wave collapse. The First Cause Must Be A Personal Being - William Lane Craig - video http://www.metacafe.com/w/4813914 As a side light to this, leading quantum physicist Anton Zeilinger has followed in John Archibald Wheeler's footsteps (1911-2008) by insisting reality, at its most foundational level, is 'information'. "It from bit symbolizes the idea that every item of the physical world has at bottom - at a very deep bottom, in most instances - an immaterial source and explanation; that which we call reality arises in the last analysis from the posing of yes-no questions and the registering of equipment-evoked responses; in short, that things physical are information-theoretic in origin." John Archibald Wheeler Why the Quantum? It from Bit? A Participatory Universe? Excerpt: In conclusion, it may very well be said that information is the irreducible kernel from which everything else flows. Thence the question why nature appears quantized is simply a consequence of the fact that information itself is quantized by necessity. It might even be fair to observe that the concept that information is fundamental is very old knowledge of humanity, witness for example the beginning of gospel according to John: "In the beginning was the Word." Anton Zeilinger - a leading expert in quantum teleportation: further note; This was not the first time Infinite parallel universes was invoke by atheists to 'explain away' the evidence; Quantum mechanics Excerpt: The Everett many-worlds interpretation, formulated in 1956, holds that all the possibilities described by quantum theory simultaneously occur in a multiverse composed of mostly independent parallel universes.[39] This is not accomplished by introducing some new axiom to quantum mechanics, but on the contrary by removing the axiom of the collapse of the wave packet: http://en.wikipedia.org/wiki/Quantum_mechanics Perhaps some may say that Everett’s Many Worlds interpretation of infinite parallel universes is not so absurd after all, if so,, then in some other parallel universe in which you also live, Elvis just so happens to be president of the United states, and you just so happen to come to the opposite conclusion, in that parallel universe, that Many Worlds is in fact absurd! For me, I find that type of 'flexible thinking', stemming from Many Worlds, to be completely absurd!!! Moreover, that one example from Many Worlds, of Elvis being President, is just small potatoes to the levels of absurdity that we would actually be witnessing if Many Worlds were the truth for how reality was constructed.,,, bornagain77

semi OT: The Big Bang, Multiverses, and the Anthropic Principle - Part 1 - William Lane Craig http://www.youtube.com/watch?v=-J5D7R3pyro The Big Bang, Multiverses, and the Anthropic Principle - Part 2 - William Lane Craig http://www.youtube.com/watch?v=jyQMGBmPkdI bornagain77

The test of a physical theory is not that everything in it should be observable and every prediction it makes should be testable, but rather that enough is observable and enough predictions are testable to give us confidence that the theory is right.

Funny, I had thought that the test of a physical theory is the verification of all of its testable predictions. EvilSnack

Sliders Niels_Bohr

I suppose that going into a wardrobe to hide, and finding oneself in a wintry glade with a lampost, would be excellent evidence of alternate universes. EvilSnack

BTW - Gil, I agree about Weinberg. Its a pity. He seems like he does not even make interesting arguments. JDH

I heard Richard Dawkins is a believer in the multiverse. So I have always wanted to ask him, "Richard, does there exist a universe where I ask you, 'Do you believe the universe had an intelligent designer?' and your answer is 'Yes'." And follow up question, "Why is this not that one?" JDH

Evidence would be another me coming to this universe to kick the living daylights out of me to become The One. tragic mishap

We need to distinguish between theory and fact. As far as I know, the multiverse is a proposed theory rather than a factual claim. The evidence for X as a theory, is that X provides highly coherent picture of the facts that are available. It's a bit like the evidence for a crossword puzzle - that everything fits so well is very persuasive, but it does not prove that there is no other solution where everything fits even better. That's the kind of evidence we would be looking for to adopt the multiverse as a theory. I doubt that there could ever be sufficient evidence to persuade us of the multiverse as fact, because any actual evidence would be evidence of this universe rather than of other universes. Neil Rickert

Here's my take: There might be multiple universes, but if they exist, based on the evidence from our universe, I would expect that they would all be like ours: rigged for life and sentient beings who contemplate such things as good and evil. I'm not in the contest. I already have my copy. I'm sorry to state the obvious, but Steven Weinberg, despite the Nobel Prize in his discipline of theoretical physics, is a real lightweight outside of that discipline. GilDodgen