• [deleted]

Dear Anthony,

I am so glad that you left a message on this blog.I've only just come across it.

I am interested to hear about your work on a past eternal model.I read the abstract but probably would not understand the whole paper.I also think it very interesting that you followed the mathematics where it went.And that you think (?thought) philosophical thinking is quite important.

I hope my essay will be interesting to you. As I intend to talk about other ways of thinking and what comes from that. I also hope you will be reminded of what you wrote here.

PS thank you for FQXi.

  • [deleted]

Paul,

This is what you said:

"... That is, there comes a 'boundary point', and that is not associated with practical issues about our ability to effect direct experience (we can hypothesise on the basis of such) but in respect of that which is never knowable (ie it is not of our existence/reality and therefore not even potentially experienceable). James had a phrase for this, something to the effect that 'one needs to allow for one miracle'. ..."

I have never said this nor do I agree with it. My point was that there is at least one 'given' for anyone's explanation of the universe but that there should be no more than that one. No additonal free-bee add-hoc inventions of the mind that continue to pop up out of a necessity generated by both early and ongoing errors. That one first 'given' is experienced by us.

Also it was part of a message that included your repeated unscientific beliefs. I don't want Louis or anyone else to think that I might think that your ideas make sense. You are certainly as welcome as anyone to express your opinions, without my retorts, as long as you do not associate me or my name with them. I understand that this has probably been a waste of my time writing this message. I expect that you will feel compelled to teach me again by repeating your errors. That effort would be a waste of your time. Please teach others.

James

  • [deleted]

James

And what is the difference between "that there is at least one 'given' for anyone's explanation of the universe" and stating that 'we can only know so much' or 'we cannot know what is not of our existence' or any other such phrase?

If you 'don't want anyone else to think that my ideas make sense', they would probably be more inclined to accept this assertion if you backed it up with evidential argument. But, as is the case with our latest exchange, you never do. Or, at the minimum you put up some comments, to which I respond, then the exchange ceases.

Paul

7 months later
  • [deleted]

Greetings folks, I see that I have come late to this discussion, but I might have a little something to contribute. I happen to have made a semi-thorough review of the philosophic literature on this topic. This is in connection with an upcoming paper. Here are some comments taken from that paper: First, theorists who have pointedly focused on the first-cause/infinite-regress issue have an almost unanimous consensus in favor of the latter (Brown 1966; Grünbaum 1989; Reichenbach 2010; Smith 2008). Thus one of the more prominent theorists associated with this issue, the philosopher Adolf Grunbaum (1989) writes: [Quote]There is nothing at all in the concept of causality as such which warrants the claim that all causal chains must ultimately originate in the finite past from a cause that is itself uncaused. Causality as such is wholly compatible logically with physical causal chains which extend infinitely into the past [Endquote]. The law of causality, in fact, only requires that each condition and each change in a condition is the result of preceding conditions. The supposed requirement for a first cause is illusory. Indeed, any supposed first cause would be, by definition, an uncaused condition. This would be the violation of causality. Nor does quantum uncertainty imply some violation of causality. More likely, this applies to gaps in our knowledge; as every student of the subject quickly learns, this is a science that is still incompletely developed at a fundamental level. Free will would imply a violation of causality, but both philosophers and scientists now have an emerging consensus opposed to this notion (Libet et al. 1983; Libet 1985; Wegner 2004; OConnor 2011; Strawson 1986; Pereboom 2001; Smilansky 2002). Likewise, a sometimes-supposed state of primordial or alternative nothingness seems to some to require a first cause. However, this can be named, but is otherwise impossible to conceptualize, imagine or even discuss in an intelligible way. It appears to be an idea completely devoid of merit (Heath 1967). The source of the supposed requirement for a first cause is apparently our everyday experiences with conceptually circumscribed causal sequences (e.g., the appearance of organic molecules as marking the beginnings of life). In fact, each such first event is preceded by additional causal conditions (with the possible exception of conditions at the moment t = 0). Most importantly, it is possible to prove in a simple way the feasibility of an infinite causal regress. Consider, for example, a hypothetical proliferation of universes as in the fecund universes hypothesis of Lee Smolin. This might be physically impossible for some unknown reason, but it is entirely consistent with causal principles. To a descendant observer infinitely remote, we would represent an infinite past. For that observer, there would have been no beginning to the Universe. (I thought references might help a little here.)

Brown, Patterson. 1966. Infinite Causal Regression. The Philosophical Review 75 (4): 510-525.

Grünbaum, Adolf. 1989. The Pseudo-Problem of Creation in Physical Cosmology. Philosophy of Science 56 (3): 373-394.

Heath, P.L. 1967. Nothing. Ed. Paul Edwards. The Encyclopedia of Philosophy. Macmillan and Free Press.

Libet, Benjamin. 1985. Unconscious Cerebral Initiative and the Role of Conscious Will in Voluntary Action. Behavioral and Brain Sciences 8 (04): 529-539. doi:10.1017/S0140525X00044903.

Libet, Benjamin, Curtis A. Gleason, Elwood W. Wright, and Dennis K. Pearl. 1983. Time of Conscious Intention to Act in Relation to Onset of Cerebral Activity (readiness-Potential) the Unconscious Initiation of a Freely Voluntary Act. Brain 106 (3) (September 1): 623-642. doi:10.1093/brain/106.3.623.

OConnor, Timothy. 2011. Free Will. Ed. Edward N. Zalta. The Stanford Encyclopedia of Philosophy. http://plato.stanford.edu/archives/sum2011/entries/freewill/.

Pereboom, Derk. 2001. Living Without Free Will. Cambridge: Cambridge University Press.

Reichenbach, Bruce. 2010. Cosmological Argument. Ed. Edward N. Zalta. The Stanford Encyclopedia of Philosophy. http://plato.stanford.edu/archives/win2010/entries/cosmological-argument/.

Smilansky, Saul. 2002. Free Will and Illusion. Oxford: Oxford University Press, USA.

Smith, Quentin. 2008. A Cosmological Argument for a Self-Caused Universe. Philpapers. http://philpapers.org/rec/SMIACA-2.

Strawson, Galen. 1986. Freedom and Belief. Oxford: Clarendon Press.

Wegner, Daniel M. 2004. Précis of The Illusion of Conscious Will. Behavioral and Brain Sciences 27 (05): 649-659. doi:10.1017/S0140525X04000159.

14 days later
  • [deleted]

Infinity is a nice mathematical concept. But when applied to anything real, any kind of infinity is just too much.

Evidences gathered so far point to a recent beginning of our universe. But what about time? If we look at our time line back to the moment our universe started... and just a bit before that... and why not a very long time before... well, there is no reason to impose a limit toward the past.

That's assuming time is a "line", a one-dimension thing which could neither be blocked by walls at its extremities nor would makes sense to loop on itself.

We can eliminate quite a few paradoxes if we consider time as a pulsation of the real. What exists is the present, and it changes at every pulsation (sorry for sci-fi writers: time machines will never exist).

Before our Big-Bang appeared, there was nothing to pulse: time did not exist yet... and when the last particle will "evaporate", time will cease to exist.

You may still use time as a dimensional continous parameter to facilitate calculations as long as this does not introduce any paradoxe. But time, really, is neither a dimension nor is it continuous. It is only ticks occuring at indeterminate intervalles.

    • [deleted]

    Oliver,

    I've been advocating that point for awhile and that the conceptual miscue is as we live lives of linear motion, we experience change sequentially, when the reality is distributed and non-linear. So rather then it be the present moving along an external vector, from past to future, it is the changing configuration, turning future into past. Not the earth traveling a vector from yesterday to tomorrow, but the rotation of the earth turning tomorrow into yesterday.

    The problem with physics is that in its obsession with measurement, it treats time as a measure of duration, which only re-enforces the narrative vector. Yet duration is not external to the present, but is the state of the present between measurement events.

    Keep in mind that "spacetime" is a correlation of measures of distance and duration. So if duration is only an effect of action and not foundational to it, then the premise of an expanding universe is based on faulty assumptions and redshift must be due to some other, ie. optical, effect.

    It is all piled rather deep at this point, so watch where you step.

    • [deleted]

    Usually, we perceive "duration" as a segment of time measured with a clock. Thus the idea of continuity, of very small (Planck scale?) segments aligned end-to-end.

    What I am suggesting is that we should consider any duration as a discrete, finite number of "ticks" which impose the same number of updates of the universe.

    The small segments are replaced by a gap of nothingness between two ticks. From the point of view of our clocks, these gaps could have a length of Planck duration, but since nothing happens to the sub-particules of our updated clock "waiting" for the updating of the rest of the universe, there is no way of quantifying the gaps themselves. We can only count the ticks.

    • [deleted]

    Olivier,

    Keep in mind the "perceiving" and thus the measuring, is always in the "present." What you are measuring is actions within that present.

    • [deleted]

    Anthony, William, All,

    Another question that might be asked is what exactly is "the past"? Or to what exactly should the term "past" refer? Is it the complete history of all events that have occurred (recoded or not), that are not also the present? Is it the data recorded, in memory and/or physical records?; or does it also included data "recorded" within the electromagnetic variations of the universe that may not have been intercepted and interpreted?

    I have differentiated these different kinds of phenomena to overcome the confusion surrounding the term "past": The complete history of all events that have occurred is the imagined complete sequence of iterations of the Object universe, up to but not including the youngest, most recent, iteration . Electromagnetic variation data, (potential sensory data), that has been formed but not yet received is called the "pre-written future", as it becomes present experience when the data is received. It is -many different potential images-, which of them is manifest depends upon the location and behaviour and type of observer.Although it is important to realise that this "pre-written future" may relate to events that occurred long ago. Only records, including memories, are categorised as "the past" within the RICP explanatory framework.They have already been present "Image reality" of a sentient being or device within our star system.

      • [deleted]

      A universe with an infinite past -history- (William's endless chain of causation) fits with the RICP explanatory framework but not a an infinite universe that has material existence spread over time, ie. a block universe. As the matter must be recycled into the youngest version of the Object universe. Otherwise there is the problem of more matter being continually produced as the universe's latest form is generated. (The "infinite number of tea cups" dilemma.)

      The image of the universe produced from electromagnetic data is a fundamentally different aspect of "the universe". The data can persist and be intercepted and formed into an image even light years after the objects and events that are encoded existed in those forms and relationships. Though it seems the existence of data from which comprehensible images can be formed is -not infinite- as the event horizon is reached and older data giving clear images is unobtainable, which makes the image universe finite. (This way of thinking about the different aspects of "the universe " overcomes the temporal paradoxes inherent within Einstein's relativity.)

      SUMMARY: Infinite history, ("infinite chain of causation"). Temporally finite (uni-temporal ie. not spread over time) material Object universe. Parts of it can not exist at different times. Finite temporal spread of space-time Image universe. (Produced from data that has persisted within the uni-temporal material universe.As it is a space-time image,different parts of the image may relate to arrangements and events that occurred at different times.

      8 days later

      Oliver, you say that, [quote] Infinity is a nice mathematical concept. But when applied to anything real, any kind of infinity is just too much[end quote]. If by this you mean that an infinite (physical) causal regress is impossible, then this is an unsupported statement. Many others have developed this position in detail, and such detailed arguments have been considered and disproven by those who have looked at the topic carefully. If you develop your argument and then look into the rebuttals in the literature, you will see that the arguments are apparently fallacious. All of the many arguments in favor of a first cause (i.e., the supposed impossibility of an infinite, physical regress) are apparently flawed.

      You also say that, [quote] Evidences gathered so far point to a recent beginning of our universe [end quote]. This involves the unsupported notion that the expanding aggregate of galaxy clusters is the Universe. We don't know that. This expanding aggregate is everything we know of, but that does not necessarily make it the Universe. Our ancestors made this same mistake over and over, and we are now doing it again.

      Analysts (typically philosophers with sometimes a strong background in physics) now have an apparent or near consensus in favor of an infinite regress. (The notion of an infinite regress is apparently paradoxical, but the notion of a first cause is highly problematic.)

      We have absolutely no knowledge as to conditions prior to about 10^-4 seconds. Implications: (1) Any supposition concerning the emergence of time and space at the moment t = 0 is speculation. (2) We have yet to identify the Universe. (If there were any preceding conditions, these are unknown, but must be included in the identification.) For the above reasons, we cannot support the statement, [quote] Before our Big-Bang appeared, there was nothing to pulse: time did not exist yet [end quote]. We simply do not know that.

      Here is another thought. Established biological principles must be consistent with principles in chemistry. Likewise, the principles of chemistry must be consistent with those of physics. Philosophy (at least in this connection) is concerned with the analysis of purely conceptual or subjective aspects of reality. In as far as philosophy produces established principles, these must be consistent with science. Therefore, established principles of philosophy can at least provide constraints on scientific theories. One of these concerns theories about ultimate origins. Philosophers have now an emerging consensus in favor an infinite regress. If you are going to reject this, you should be prepared to show where they have made a mistake. You need to prove that a first cause is possible. You might be tempted to start by rejecting causality itself, but keep in mind that this has been tried, and it is an apparent failure.

      • [deleted]

      Dear All,

      There is no space unless one chooses to measure and there is no time until one chooses to count, there is no spacetime besides one absolute self.

      "Consciousness is the sphere of universal schwarzschild radius (ranging from zero to infinity) with a central cosmological constant of conscience (i)" - iSphere.

      zero = i = infinity

      Love,

      Sridattadev.

      5 months later
      3 months later

      Cosmology topic: Is the past infinite?

      My viewpoint on this is based on a new theory of The evolution of the universe

      The theory proposes a space boundary as well as a time boundary. The universe has a past time boundary at time zero but because the expansion of the universe is caused by the expansion at the space boundary there is no future time boundary.

      The universe is defined at all points within the spacetime boundary so that at any point T1 it will always be possible to find an earlier time T2 lying within the spacetime boundary. Space and time are only defined within the boundary so the hypothetical time zero could never be reached by this method. It is also possible that the rate of passage of time slows at the approach to time zero due to the effect of spacetime curvature.

      Richard

      5 months later

      I think the primary reason researchers have theorized exchange, parallel or digression universes need to do with the effects of twofold opening investigations. In my model, our universe is a piece of a more amazing fractal universe. Our universe exists between the scale of the Planck length and that of the vast froth. Our grandiose froth (having an average air pocket measure about 10^24 meter over) is the ether froth of a super-universe; our ether froth (having an average air pocket estimate approximately 10^-35 meter over) is the infinite froth of a sub-universe. Connection between scalewise universes must be deduced; it can never be specifically watched.

      Online Math Practice

        18 days later

        Alice, what do you think of the following?

        String Theory and subquantum scale atoms

        (Human scale mass 57.768 kg)/(neutron mass 1.675 x 10^-27 kg) = 3.449 x 10^28

        (Human scale mass 57.768 kg)(3.449 x 10^28) = (Solar System mass 1.992 x 10^30 kg)

        Human consciousness resides midway in scale between quantum & cosmic scale masses.

        Diameter of 1.992 x 10^30 kg concentrated in a sphere at atomic densities equals ~ 7.6 x 10^8 m

        Neutron diameter ~ 2.0 x 10^-15 m

        ツ・L = Length scaling factor between the quantum and cosmic scales = 7.6 x 10^8 m/2.0 x 10^-15 m

        ツ・L = 3.8 x 10^23

        In string theory particles are perceived as highly localized vibration of Planck length strings.

        lp = (トァGc^-3)^1/2 =

        [(1.0546 x 10^-34 Js)(6.6742 x 10^-11 Nm^2/kg^2)(299792458 m/s)^-3]^1/2

        lp = 1.62 x 10^-35 m

        From the Bohr model of the Hydrogen atom and in particular quantized angular momentum:

        mvnrn = nトァ

        Combined with the de Broglie relation: ホサ = h/p

        The relation has long been known: 2マ\r = nh/p = nホサ

        The smallest atomic orbital circumferences are the ground state Helium shells (1s^2 orbital) of the heaviest atoms. The diameter of the helium shell for Radon (z = 86) ~ 0.02 テ.... This shell has an average circumference =

        2マ\)(1 x 10^-12 m) = 6.28 x 10^-12 m, which is also the smallest ground state wavelength of an atomic orbital in the human scale.

        Length scaling factor: ツ・L = 3.8 x 10^23

        A self-similar Radon atom existing at the subquantum scale will have a self-similar subquantum scale 1s^2 orbital circumference measured relative to the human scale:

        6.28 x 10^-12 m/3.8 x 10^23 = 1.7 x 10^-35 m

        Vibrating string particles correspond to subquantum scale atoms.

        Strings are subquantum scale atomic oscillators.

        4 months later
        • [deleted]

        The crisis in the fundamental physics, including cosmology - the "crisis of interpretation and representation" (T.Romanovskaya), the "crisis of understanding" (K.Kopeykin), it is the crisis of the philosophical foundations, especially in understanding of space and time.

        The way to overcome the crisis - is a further deepening of the Geometry, but rather in the "origin of Geometry" (E.Husserl) and the dialectico - ontological unification of matter, search for the absolute foundations of physics and knowledge, the absolute generating structure. Necessary to consider limiting (absolute, unconditional) state of matter: absolute motion (rotation, "vortex", discretuum) + absolute rest (linear state, continuum)) + absolute wave ("figaro" of states = discretuum + continuum).

        Then geometrized basis: "sphere" + "cube" + "cylinder". Each limit (absolute, unconditional) state of its way - the absolute vector, the vector of the absolute state. This "triangle" of absolute states of matter - the ontological representation of the triune foundation - "origin of geometry",» the beginning of physics, the beginning, framework and carcas of knowledge. This is what David Gross calls - "general framework structure" (D.Gross, an interview "Iz chego sostoit prostranstvo-vremya/What is in the space-time) the same for the QM and for GM. Today QM and GM are parametrical theories without ontologic justification.

        Semantically poor picture of the world "In the beginning was the Big Bang" should be replaced with a picture of the world "In the beginning was the Logos (MetaLaw, the "law of laws")...", the base of which the "General framework structure" or the "Absolute generating (maternal) structure" . This is the «Cosmic Origin».

        Should always be keep in mind the philosophical covenant of John Wheeler:

        "Philosophy is too important to be left to the philosophers".

        It would be nice if FQXi will hold the new contest of cosmological models: «Cosmic Origins». In the world today there is a lot of alternative views and models , other than «the classic big-bang model».

        Carlo Rovelli made a good conclusion in the article SCIENCE IS NOT ABOUT CERTAINTY: PHILOSOPHY OF PHYSICS :

        "This is a standard idea of how science works, which implies that science is about empirical content, the true interesting relevant content of science is its empirical content. Since theories change, the empirical content is the solid part of what science is. Now, there's something disturbing, for me as a theoretical scientist, in all this. I feel that something is missing. Something of the story is missing. I've been asking to myself what is this thing missing? I'm not sure I have the answer, but I want to present some ideas on something else which science is.

        This is particularly relevant today in science, and particularly in physics, because if I'm allowed to be polemical, in my field, in fundamental theoretical physics, it is 30 years that we fail. There hasn't been a major success in theoretical physics in the last few decades, after the standard model, somehow. Of course there are ideas. These ideas might turn out to be right. Loop quantum gravity might turn out to be right, or not. String theory might turn out to be right, or not. But we don't know, and for the moment, nature has not said yes in any sense.

        I suspect that this might be in part because of the wrong ideas we have about science, and because methodologically we are doing something wrong, at least in theoretical physics, and perhaps also in other sciences."

        So, in the search for primordial structure of the Cosmos (Universum).

        Regards,

        Vladimir Rogozhin

        2 months later

        http://www.academia.edu/8991727/Phenomenal_World_as_an_Output_of_Cognitive_Quantum_Grid_Theory_of_Everything_using_Leibniz_Kant_and_German_Idealism

        20 days later

        JUST BEFORE THAT BIG BANG WENT KA-BOOM

        Once upon a time, or was it in the beginning, there was a Big Bang and thus was born what we now call our expanding Universe - expanding because really Big Bangs are associated with explosive events and explosive events hurl out stuff hither and yon. But while there's little dispute about the Big Bang event, the central question is, was it an 'in the beginning' event, or more akin to a 'once upon a time' event? If the latter, then it's reasonable to suggest there was a prior existence to that 'once upon a time' event.

        I've gone on and on about how there must have been a 'before-the-Big-Bang', that the Big Bang event 13.7 billion years ago wasn't the first cause. That's because no effect (in this case that Big Bang event) can be the cause of itself. Cause is external to, separate and apart, and prior to the effect. Now it's time to explore some actual before-the-Big-Bang scenarios even though there are still, even the majority, of cosmologists who suggest that speaking of a before-the-Big-Bang is akin to speaking of what's further down from the centre of the Earth, or what's north of the North Pole.

        Astronomers can't see deeper into the history of our Universe than roughly 380,000 years after the Big Bang event. Until then, the entire Universe was still too opaque. It's like the Sun being too opaque such that we can't see beneath the visible surface all the way down to the core. So it's obvious that if astronomers can't see post the Big Bang to the tune of some 380,000 years on, they can't see before-the-Big-Bang. However, I'm quite certain there was a before-the-Big-Bang and that our Big Bang event was just one local cosmic pop in a cosmic ocean of bursting Champaign bubbles.

        To understand the Big Bang event one needs to understand (as best as one can) what transpired just before the Big Bang event. And for reasons already outlined, what happened before exists in the realm of scientific speculation.

        First cab off the rank, here's a brief explanation why there has to be a before-the-Big-Bang. The Big Bang event did not, could not, create time. Although astronomers suggest just that, when it comes to actually giving the recipe for cooking up a batch of time, our astronomical chefs' duck back into the pantry. So, IMHO, time already existed at the moment that the Big Bang went 'bang'. The Big Bang could only happen in time if time already existed, which means that time existed prior to the Big Bang in order for the Big Bang to 'bang' in or at the time it 'banged'.

        As an aside, if our Big Bang wasn't a first cause, then one is hard pressed to say there ever was a first cause for reasons exactly similar to why our Big Bang wasn't the first cause. There always was a 'before' for whatever first cause you wish to postulate, therefore your first cause wasn't a first cause at all. The regression extends back infinitely. If the cosmos extends back infinitely, it stands equally to reason that the expanding cosmos will extend for all future infinity - for all eternity. As a theological aside, that eliminates the need for a creator god. It's been said before, but it bears repeating that if you have a timeless, existing for all eternity, creator God who created the Universe, why not eliminate the middleman (God) and postulate a timeless, existing for all eternity, Universe? By the way, a similar argument can be made for space. Anyway, back to the before-the-Big-Bang.

        One aspect that's important from the get-go is that one needs to avoid the trap into thinking that the before-the-Big-Bang to Big Bang transition resulted in something quantum sized, like a singularity, at that point of inside-out transition. There just is no way IMHO one can take the contents of our entire Universe and squeeze that down into a size that would make a pinhead look massive in comparison. In addition, the laws of physics break down at such a scale since there is no adequate theory of quantum gravity. You'd require such a theory since 1) you're postulating a quantum sized object, and 2) because the entire Universe makes for a lot of gravity, that's a lot of gravity in an extremely tiny space. Since it can't be done (and thousands have tried to merge quantum physics with general relativity (gravity), it's best to bypass that can of worms entirely, if possible.

        When you think of bangs today, big or otherwise, it's usually by something that's been sitting around for a spell just waiting for a triggering device like an about to be blown tire; about to be popped balloon; about to be exploded stick of dynamite, nuclear bomb, or supernova, etc. So, maybe our before-the-Big-Bang was akin to a giant firecracker just waiting for some before-the-Big-Bang happening to light the fuse. The one scenario that fits that bill is the Ekpyrotic Universe which basically states that there exists a minimum of two 3-D universes each existing in a higher dimensional space. That means the two universes don't actually see each other since photons can't pass through that higher dimension. However, gravity can pass through the higher dimension so the two universes can feel each other Thus, these two universes mutually attract under gravity, collide (our Big Bang and equally their Big Bang), and bounce apart - rebound. That process repeats at vastly lengthy intervals as gravity draws them together, again, and again and again (more Big Bangs) and then each rebounds, again and again and again.

        The closest celestial firecracker we have is a supernova. Unfortunately, even the mother of all supernovas isn't quite in the same league as the Big Bang event. It's like pitting the Little Leagues against the Big Leagues.

        A more theoretical firecracker might be the mother of all Black Holes which at some point reaches and exceeds bursting point vomiting out in reverse order its contents. That theoretical object is a White Hole, like perhaps a quasar (quasi-stellar object). Quasars spew out lots and lots and lots of stuff and energy all from a stellar-sized object. But that scenario too falls short of the amount of stuff comprising our Universe. It seems only the stuff of another universe could account for the amount of stuff that was 'created' to make our Universe. The one fly in the ointment here is that a singularity might lay at the heart and soul and centre of any proposed Black Hole and I wish to avoid that can of worms as noted above.

        The other kind of 'bang' expansion is say, using as an analogy, traffic approaching and merging at a four-way intersection. That's the contraction bit. After the traffic lights change, the traffic is free to go on its way. That's the expansion bit. There's no real 'bang' per say. In other words, the Big Bang was the transition of space turning itself inside-out as it were. Either you had the collapse of a previous universe that went through that four-way intersection, or something akin, like a Black Hole that's vomited up its contents in the form of a White Hole, sort of like post Xmas sale shoppers rushing the external department store doors and then being 'vomited' out the inside of those department store doors and expanding into and throughout the store.

        The more logical of the two scenarios is the latter. That's because we know that any universe is inherently unstable. You just can't have a perfectly still and static universe if for no other reason than gravity will pull all the flotsam and jetsam together, or in other words, a contracting universe is viable and likely.

        The fly in that ointment is that the alternative, an ever expanding universe is also viable and likely if the oomph force that caused the initial expansion is stronger than gravity's grabbing force.

        We can garner some insight as to whether the immediately pre-Big Bang era was hot or cold. If the Big Bang was an in-place explosion, well most explosions involve giving off heat, be it sodium placed in water (ka-boom), a firecracker (ka-boom), an atomic bomb (ka-boom) or a supernovae (ka-boom), these all appear to be exothermic reactions - they give off heat. However, an explosion in waiting is a much cooler state of affairs. While holding a firecracker in your hand won't burn your hand, the same cannot be said if it goes bang while you're holding it. So the pre-Big Bang era wasn't exactly hot stuff.

        If the Big Bang was the result of a previous universe contracting, like cars approaching an intersection from all four directions, well the very act of compression heats things up. So, the Big Bang was a hot (time in the old town tonight) event, and therefore just before the Big Bang was also pretty heated.

        Well, maybe we can't garner any insight after all since the era just before the Big Bang may have been hot or cold. But the Big Bang itself was a high temperature event no matter which way you slice and dice things which is good since that's what you'd expect from the observational evidence.

        What about entropy? Our Big Bang Universe started off in a state of high temperature, a state of high order, or in other words low entropy and has been going downhill (cooling off) ever since. That is, the Universe is becoming more disordered as it heads towards an inevitable heat death. A heat death means that the entire Universe is now at the same temperature and no further cosmic evolution or change can happen. But if our Universe started off in a state of high order, then the pre-Big Bang phase must have been in a state of high order too. Well, high order would have been the order of the day in either of the two pre-Big Bang scenarios.