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Author Topic: Causality, the Big Bang, and the Shape of the Cosmos  (Read 2067 times)

Offline AndroidNeox

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All of science is based upon the presumption of causality. Many people don't recognize this but that's just because logic and natural philosophy seem to be out of vogue. Without the presumption of causality, there is nothing to connect observation to event and no justification for the belief that mathematics can describe reality.

However, when we look at cosmic history, causality breaks down at time = zero, about 13.8 billion years ago. After puzzling over how to proceed from such a situation I decided to attempt to learn from a master reasoner, Einstein. When faced with the problem that the speed of light seemed to be required to be a constant for all observers (which made no sense in terms of Newtonian physics), he just accepted it as a given and reasoned that space and time must adjust to keep c a constant. So, I reasoned, what if the situation prior to time = zero was non-causal?

Causality is all about conservation symmetries. In fact, every physical law we've found can be described as a conservation symmetry, which is apparent in the quantum mechanical "eigenmatrix" for any system and the fact that they must be Hermitian. A non-causal condition would be free from causal constraints... no limitations on getting something from nothing and/or nothing from something. There couldn't be anything like time or space, but there could be an infinity of anything. Chaos. Not the mathematical chaos of systems that are actually deterministic but so heavily dependent upon initial conditions that they are unpredictable. Real chaos with no rules.

It occurred to me that such non-Hermitian quantum states might not be impossible. Schrödinger just stated that such systems are unobservable. Maybe this requirement of quantum mechanics provides a filter so that an observable universe can find itself within a limitless complexity of information (or quantities... I find Wheeler's "It from Bit" idea compelling).

Schrödinger stated that quantum systems for which the physical symmetries do not balance, systems whose quantum state matrix is non-Hermitian, are “unobservable”. So, I took that as literal. I assumed everything quantum mechanics describes (a virtual infinity of allowed states, supported by evidence such as Bell’s Inequality) exists but that something about the nature of observation (causality) filters out anything that doesn’t fit. It would provide a mechanism so that, even within a chaotic froth of infinite information, every observer would experience only causal consistency.

Not only would this provide a universe, it would provide for a complete multiverse, with every observable reality instantiating. Every observation by every possible observer could instantiate, which is all you really need since, for all observers, observation defines existence. In fact, every possible combination of mutually-consistent physical laws could instantiate. Instead of our universe, able to support sentient creatures being unlikely, it would be inevitable.

Given that any such observable system must adhere to some set of conservation symmetries, where does the matter come from? Causal systems can’t get something from nothing… at least, something from nothing cannot be observed. So, the new matter must appear at the observable horizon.

Because no entanglements extend across the observable horizon, quantum mechanically, the horizon must appear as a black body. If you model a very small universe, the horizon will be very hot. In quantum mechanics there is currently a (mis)understanding that space at very small levels must be a high-energy froth, which doesn’t match observation. The problem is, instead of modeling a small part of a large vacuum, which would correspond to our current universe, they are modeling a small universe. The error comes from forgetting that what is observable is determined entirely by the set of entanglements within the system. A small portion of a large vacuum will be entangled with a large empty region… from which it’s unlikely any matter will impinge on the small vacuum being examined. I can explain this more if anyone’s interested. It’s just a problem of not using the right physical model for setting up the equations.

But, our young and small cosmos would have had very hot horizons, just as QM predicts. The horizons would cool as space expanded.

Also, because this model, in which all physics is local to the observer must satisfy conservation symmetries, the resulting cosmos should be expected to look just as ours does, with no net spin, no net electrical charge, and spherically-symmetrical.

Just presuming causality can get one from a non-causal condition to the universe we see. It’s a very powerful rule and I think it deserves greater consideration.


 

Offline David Cooper

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Re: Causality, the Big Bang, and the Shape of the Cosmos
« Reply #1 on: 03/12/2013 18:58:40 »
With Einstein's model there is no causality at all, and here's a thought experiment that demonstrates it. Imagine that a photon is sent out from the Earth and travels away into space, then it hits a mirror on an alien world and is bounced back by luck towards where the Earth will have moved to, whereupon it lands right back on the Earth where it started. For that photon, no time has passed - it has taken a shortcut into the future. How much time has gone by on the Earth in the meantime? A billion years. A billion years' worth of events have gone by on the Earth in what for the photon is zero time. This destroys all the causality in the astronomical number of events that have taken place on the Earth during that billion years, because the photon has bypassed the billion years and stepped straight into a pre-built future in which all the effects of the causes have already been settled without any cause-and-effect processes having to work through. In this magical model, effects are not caused by their supposed causes, but are there by luck alone.
 

Offline AndroidNeox

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Re: Causality, the Big Bang, and the Shape of the Cosmos
« Reply #2 on: 11/12/2013 19:31:50 »
With Einstein's model there is no causality at all

Causality is covered by the Relativistic requirement that all frames of reference are equivalent for observations.

You present an interesting argument that the fixed and unchanging spacetime required by non-simultaneity, a consequence of Relativity, doesn't conform to the customary view of causal events, there's nothing about it that eliminates causality. It might, as Einstein feared, leave no room for "free will" but the constraints of causality fit within it.
 

Offline David Cooper

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Re: Causality, the Big Bang, and the Shape of the Cosmos
« Reply #3 on: 11/12/2013 20:21:18 »
If you start with a universe in which events have never played out, if a photon can travel a billion years into the future in zero time, any apparent causality in the billion years' worth of events that from the photon's point of view have taken place in zero time cannot be real - there was no time for any cause-and-effect processes to work through. It only works if the future events have already played out before the photon makes its trip, but if that's the case, when those events originally played out the photon must still have been involved, and it would have to wait a billion years after starting its trip before it could complete it. Once the future has been processed into existence, you can then play games in which you imagine photons making billion-year trips in zero time, but it doesn't work when the real physics is acting on the original creation of that future. The reality is that Einstein's model doesn't work unless you add a Newtonian time to it in addition to its three space plus one "time" dimensions. Having introduced that essential Newtonian time to the model, it now makes full sense to talk about what happened before the big bang and what may have caused it.
 

The Naked Scientists Forum

Re: Causality, the Big Bang, and the Shape of the Cosmos
« Reply #3 on: 11/12/2013 20:21:18 »

 

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