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What does it even mean to ask “what happened before time”? The question seems nonsensical to me.

• sp332 7y ago
  You can still have causality.
  • pavel_lishin 7y ago
    Can you expand on this? How can you have causality - cause and effect - that's divorced from some sort of flow of time?
    • kowdermeister 7y ago
      If I turn on a very simple computer, then the clock starts at zero. From the computers perspective that's all there is, it doesn't know the cause. From my point of view there absolutely is a case, me pushing a button. This is not a god argument, there might be natural processes that can trigger such events.
      • pavel_lishin 7y ago
        The computer, and the external universe of which it is unaware, still have time.
        • Cyph0n 7y ago
          Total amateur here: how do we know that time did not exist before the beginning of the universe?
          • AnimalMuppet 7y ago
            Almost-total amateur here: We don't. We really don't. We don't have any physical evidence of anything from before the big bang (presuming that's what we call the "beginning"). Zero. All we have is people having views on the current situation, trying to apply those views backwards to "before", where they may or may not fit, and saying "I think it's like this".
      • wuliwong 7y ago
        I don't think this is an accurate analogy. The computer's space-time and your space-time are the same in this analogy. The space-time that our universe exists in would not be the same as the space-time that some extra-universe process would be inside if the big bang theory is accurate. This isn't an analogy for causality without time, this is causality for the creation of our universe if the big bang theory is wrong and space-time didn't expand out of a point some billions of years ago, ie. that our space-time existed "before" the big bang and there were processes outside of our universe that were still inside of the same space-time as ours.
        • TheOtherHobbes 7y ago
          If the computer is simulating a spacetime, they're not the same. You could - hypothetically - pause the computer, check its state, change a few variables, and the simulation would experience instant modifications. A slow simulator could take many "real" time units to calculate each in-simulation time frame - and this would be invisible in-simulation. And so on. You have a fully causal system, but the simulation is ruled by its own independent emulation of causality. Of course a computer implies a conscious user. But let's attempt some wild speculation and suggest that a "simulation" could also be a completely natural process - something that happens in a much bigger causal substrate: a kind of causal symmetry breaking, where a subset of possible relationships crystallises out of a bigger set of possibilities and then continues independently, losing some degrees of freedom. A simple two level topology is the simplest possible model. But "causality physics" could allow all kinds of topologies - nested, circular, fractal, etc.
        • burlesona 7y ago
          Although it raises an interesting question, because physics has a lot of issues with time. Just as in the computer example, why could we not imagine that our universe exists inside the space and time of larger superuniverse, and perhaps the phenomena that explain times arrow is easily observable in that universe, but not in ours.
        • karmakaze 7y ago
          Good point which brings us to a simple explanation. Time zero isn't when the h/w is booted, it's when the software is started. As unpopular as the simulation theory is, many difficult issues can easily be thought about. Except for the rest of the turtles.
    • abtinf 7y ago
      Logically, cause and effect precede time. The concept of time integrates your perceptions of cause and effect. We observe various causes and effects require variable amounts of time, we omit the specific amounts of time, thus inductively identifying the abstract concept of time.
    • 0815test 7y ago
      Both causality and the "flow" of time are ultimately artifacts due to the fact that a "universe", by definition, is something thay starts out in a highly-ordered state and evolves away from it. The basic laws of physics are time-symmetrical, at least in a practical sense - they do not involve any distinction between "cause" and "effect".
      • AnimalMuppet 7y ago
        > a "universe", by definition, is something thay starts out in a highly-ordered state and evolves away from it. I don't think that's "by definition". That's by observation of an example of one.
    • bduerst 7y ago
      Our existence is limited to four dimensions, so we perceive things through the scope of time, including cause -> effect. On the level of higher dimensions, it's difficult for us to perceive how cause -> effect would play out, but it's similar to how you would influence a drawing of a 2D stick figure. You could draw a house next to the stick figure, and that would cause the house to exist, but to the stick figure it would only perceive a single line with a start and finish on 1 dimension. To that stick figure, cause and effect would be perceived as the two points on the line, though your four dimensional pencil caused it to exist on a different dimensional level.
    • antidesitter 7y ago
      According to some theories, space and time arise from causality. https://en.wikipedia.org/wiki/Causal_sets https://en.wikipedia.org/wiki/Causal_sets
    • xenocyon 7y ago
      Causality is just human perception and there's nothing special about time. Let me try to explain this in three ways, going from intuitive/trivial to non-intuitive/mind-blowing: • You can have causality in space rather than time: e.g. a convolutional image filter at pixel 13 might consider pixels 12, 13, 14 (of which the first two are causal and the last is non-causal, if we consider higher numbers as going "forward") • You can have non-causal filters in time: e.g. audio compression at time 0:30 might consider not only the portion of audio from 0:00 to 0:30, but also the audio from 0:30 to 2:33. (This doesn't seem that remarkable, because the track has already been recorded, so it's not in "real time".) • Finally, what we usually think of as intuitive causality in "real time" is simply a question of entropy. We think of a person dying because she was shot by a bullet, but we could also replay the movie backwards and think of all the tissues of a human body coming together in such a way as to propel the bullet backwards at a high velocity - in other words the wound causes the bullet to fly! The only reason we don't think of it this way is because the latter explanation decreases rather than increases entropy. As it turns out, physicists can show that entropy is also the exact reason why we remember the past and not the future. (And if we did remember the future and not the past, we would simply think of the future as the past and vice versa, so things wouldn't feel any different.)
  • quotemstr 7y ago
    Causality without time makes no sense. Even if you don't have a ticking clock, you can define "time" with a counter and a Lamport clock. Any time you have state, you have time. A timeless universe is hard to grasp.
    • abtinf 7y ago
      Time without causality makes no sense. Time is an identification that entities move and change. The entities themselves cause all actions. The nature of those actions is determined by the nature of the entities.
    • morsmodr 7y ago
      Time is another dimension that we 'perceive'. Hence for our frame of reference, which is bound by time, asking what is outside this frame of reference makes no sense. But frames of references are relative and meant to be broken. Similarly it is hard to imagine any object that can be purely 2D in nature, because we are biased to perceive the world in 3D. So we think that every object has to be 3D, even the smallest organism, or even atoms. But a 'fake' example of 2D is a tv screen. It gives us an example to imagine 2D. The point I am trying to make is that time is just our perception. To say causality is always tied to time is a bias created by viewing the universe through a 'time' tinted/colored glass. The point of singularity where gravity is so high that time comes to stand still, but is still present - this is a possibility. So maybe time just pauses between big bangs and flows at lower density and lower gravitational fields
      • SomeOldThrow 7y ago
        > The point I am trying to make is that time is just our perception. So is causality—I'm not really sure what your point is.
        • morsmodr 7y ago
          Because we are limited by our perceptions of time (and causality as well) doesn't mean we shouldn't wonder what could have been before the start of the universe. Maybe time started when universe started, or maybe time always existed and was super slow or literally paused at singularity - the gravity is so high (way more than the gravity of a super massive black hole) that time had paused. So maybe there was something before the big bang and I don't think 'talking about that makes no sense' should stop us from talking about it :) I am also confused a tad about the point I wanted to make though, lol. Maybe causality and time is perceived differently in higher or other dimensions that we do not perceive as of now in our human level of evolution. So the assumption of causality exists only due to time being present could be something relative to our perceptions and not true
  • deleted 7y ago
    [deleted]
• ASalazarMX 7y ago
  It's nonsensical to wonder what happened in our universe before it existed, but if our universe has an external superuniverse, it's not illogical to wonder what happened there that caused our universe to exist.
  • erikpukinskis 7y ago
    Can we follow this a little further? Let’s say you and me are little bits of algae which are floating in blob in the ocean off the coast. We are in a larger current which we cannot see. The current is such that we will eventually strike the shore together. We are in a cluster of material together. It’s not exactly algae, there are a bunch of random gels, some mostly decomposed skin parts. Some very fine grit. Of course the ocean is constantly mixing everything up, so even though we have been in this blob together for several weeks, that’s not exactly normal. Well, there millions of blobs like ours, so I guess it’s sort of normal. But there are a quadrillion billion blobs that won’t last the hour. So our blob is, if not abnormal, improbable. You and I are algae, so we can’t sense much. But we have noticed many events over our lives. Very early in our lives we perceived the day cycle. There are good times to photosynthesize, boy did we feel that. Time. We noticed quite a few bacterial... situations. And geometrically there have been a number of events in our blob. It used to be much bigger, for one thing. We certainly noticed every time a chunk got taken out of the blob and the energy gradients went haywire. Of course we’re algae so we don’t remember, but we notice. There is a world outside our blob, but we cannot know it. Sadly, this is physics. There’s not enough atoms in the blob to make a fin, let alone an eye or a brain. So there will be no peering out of the water at the sky. We can sense events within the blob. Outside the blob there may be more going on, but we certainly can’t see it. There are unexplainable patterns in the blob. Why does it look sheared off on two sides? “We”, meaning our limited algae consciousnesses, didn’t exist during those events so we are just as cut off from our past as we are cut off from the world around us. And we are barreling now, in a wave towards the shore. And now we are floating. And now we are rolling through a wave towards the shore. And now we are slipping calmly on the surface. And soon we will crash onto the sand, where we will be consumed by bacteria and insects, and our blob will be no more. It is inevitable. The first law of algae says: you will be eaten. But we will not be eaten this minute. And so I ask you: what happened in the blob, before it existed? Luckily, though we can’t see outside the blob, we can ponder questions like this, because we are hypothetical blobs, and hypothetical blobs have human brains! We can certainly guess what our bodies were before the blob existed. They were a cloud phosphorous and nitrogen. And presumably there were other plants or bacteria in our proto-blob that produced those nutrients for to become us. That bit of skin I mentioned was on a dead whale. It was on the ocean floor but it got kicked up to the surface in a storm. The gels came from jellyfish. And the salty water around us... well, it was salty water. What shape was all that stuff in? A strange one. But still, we could draw it if we had some art supplies. And fingers. The current that brought in the whale skin could be drawn to an approximation. The bacteria largely came from two identifiable blooms, plus a long tail of about a thousand others, plus an unknowable tail catalog of origins describing the last 0.001% of bacteria in our blob. We couldn’t draw that, but maybe a light watercolor fog around our greater vicinity could represent it. If I could draw our blob before it existed, it would look like a strange flower. With very long tendrils but also several beautiful simple twisted surfaces. Now, what about the universe itself? Science suggests its origins were not nearly so “soft”. Our blob was sort of “assembled” from pre-blob parts. The universe doesn’t appear to have been assembled in a soup that same way. Trend lines suggest it started as a singularity, not an assemblage. But all physicists will admit we don’t have the technology to peer into those first moments. Like us and our blob, there’s just not the equipment available to look outside the universe to get data, nor was there equipment present to remember things as they happened. We just don’t know what physics is like in those kind of moments. Is it an assemblage of parts from a larger vicinity? Are there even larger vicinities than our blob? Or, to put it in terms that you and I would understand: did the universe, at birth, have a bit of whale skin in it? Some dead jellyfish bodies? We can only speculate. As for me I say: why not? But I’m just a bit of algae. What do I know.
• MrQuincle 7y ago
  It might be phrased differently. Like this. Is there something more universal than time. Look at spacetime from an outsider's perspective. Suppose it is 2D+1D, then one way time can be represented is as frames where each frame is slightly different. The interesting part is that those consecutive frames have very strong constraints. But what are those constraints? One of them is that energy is conserved. One other might be that it's Markovian: you only need to have the last frame for the next. If there exist (entangled) histories this seems to be wrong. The quest for (moderately) consistent frameworks that all have their own emergent nature of time might be a very fruitful one. It's rather a "beyond" time than a "before" time.
• karmakaze 7y ago
  It helps to think of time as change. Time started when the first thing changed. So to say there was no beginning helps by not having to answer what the first change was ot why it did. It's still hard to imagine no first change without an infinite regress. Maybe if you think of it reletivistically as in there wasn't a singular beginning but a beginning area where depending on where you are it could be a beginning but not the beginning.