Can you guys stop making so many sensible comments that deserve thoughtful replies? It takes me a lot of effort to reply in kind
(seriously, I'm impressed)
out of whack said:
These theories of course are based on known science, which is based on the universe as we know it today, and this is perfectly reasonable when your aim is to understand the known universe.
Which is what I thought we were doing…
But since we have no information on what came before the Big Bang (if anything, more on this below) then science cannot address that part, which is central to our discussion.
I would still like to keep a distinction between the universe as perceived through our senses (stars, planets, space, time, etc), and whatever else can be said to exist. I'd like to call the former "universe" and the latter "reality", which is what I believe those terms mean (I may be mistaken though; who knows for sure?)
So are we discussing the universe or are we discussing reality? It seems you agree the universe had a beginning while reality is eternal. In which case, as I stated a few times already, I don't think we disagree at all.
Will you reject a logical argument if it conflicts with your understanding of a scientific theory?
That is not always a simple choice. Rejecting a scientific theory on the basis of logic alone is what turns a lot of people into crackpots, and a few of them into heroes.
If so then I may in turn have a problem with your reasoning.
You want me to talk like a crackpot? I'm quite good at it
My position is that since science must be logical then logic must win over science if there is a discrepancy.
If only things were that simple…
The problem with logic is that we seldom fully understand what we are dealing with. As a computer programmer, many times I stared at the screen in disbelief at what I was seeing; logic told me the program should do one thing, and it was doing another which made no sense. Yet 10 times out of 10 there was a small detail I failed to consider.
When it comes to logic versus science, nature is the computer, in the sense that nature never makes logical mistakes. You may not always understand why you are not seeing what you expected to see, but you can always be sure it's your fault.
Let's back up to the time of zero entropy. We have all this fully useable energy bottled up that undergoes the very first change: bang, entropy is suddenly non-zero following the very first thermodynamic change. Since you say that a
change in entropy is the passage of time itself, this has to be the beginning of time.
Yep.
Since you also stated that reality existed for all time then this first change must also be the beginning of reality, which coincides with the beginning of the physical universe.
My understanding of reality is that it does not exist in time, because it never changes. It's not correct to say "reality existed for all time", but rather "reality creates our perception of time".
if the entropy level was quantifiable (existed) and if the energy of the universe after the first change also existed (and was quantifiable at that time) then the initial energy is clearly quantifiable as well, meaning that something quantifiable existed before the beginning of reality and of the physical universe.
Not before. "Before" implies time, and you can't measure time without entropy change. There is no "before" the universe began, we use that word for lack of a better concept but we can't really speak of time without physical activity.
Consider a circle. You can talk of circles of different sizes, and you can think of circles expanding and contracting, but even though there is no limit for expansion, there
is a limit for contraction. Once the radius becomes zero, the circle can no longer be contracted. Because of that, it makes no sense to talk about a circle of negative radius. You can make sentences using the concept of negative radius, and they appear semantically correct, but they are meaningless.
This is the sense in which I see the concept of time. It has no limits one way, but it must necessarily be limited in the opposite way, otherwise it becomes meaningless. Sure, we can talk about "time before the universe began", we can make up the concept, but unless we can explain what it means in terms of other concepts we already understand, it means absolutely nothing.
You explicitly restrict what is quantifiable to only our current interpretations of the universe.
That is because "quantifiable" is part of our current interpretation of the universe. Your complaint is equivalent to saying I'm explicitly restricting the meaning of the word "quantifiable" to our current interpretation of the English language, and that is an error because there may be languages which use the word "quantifiable" with a meaning that is different from English.
The basic error you are making is that you are mentally positioning yourself outside the universe as you currently know it, and trying to describe what you see. You cannot do that. Wherever you go you take your current knowledge of the universe with you, so you shouldn't be surprised you always see the same things.
The correct way to understand this issue is not by looking at the universe, but by looking at what we are left with when we ignore the entirety of our knowledge. And here you inevitably fall into some form of mysticism.
I cannot discuss the origin of the universe if you use "nothing" to refer to whatever science cannot handle.
You can also use "God" if you want. Or "The Great Unknown". Or any other concept from mysticism. Really, there is no way to avoid it.
It makes it a tautology that the universe began with the first event that can be addressed by science.
Which is great, because as you know all tautologies are true
On to the next...
JonF said:
No it isn't, sets are abstract objects.
We have to be careful with words as we often fool ourselves with the way we use them. Sets are abstract objects, but we often refer to the "members of the set" as "the set". It would be tiresome to be explicit all the time, but sometimes we lose sight of what we really mean.
Surely seeing the universe as a set is an abstraction, but an abstraction is just a shorthand for something else.
Physics and math are both similar in the respect that attempt to draw deductive conclusions from a well defined system of assumptions. The big difference in math these assumptions are arbitrary, and in Physics there is an attempted to make them correspond to the real world through experimentation.
This reminds me of that joke where the rector of an university asks why the physics department spends so much money on lab equipment. He says, "why don't you guys do like the mathematicians, who only need paper, pencils, and a wastebasket? Or better, like the philosophers, who only need paper and pencils!"
Mathematicians don't make arbitrary assumptions, only philosophers have that privilege (it's curious that not even theologians have such freedom as they are bound by scripture - philosophers really have it easy). Mathematicians are constrained by the requirement that the whole body of mathematics must be self-consistent. That leaves them with a very limited number of possible axioms.
Physicists are of course constrained by the universe, but the only difference between math and physics is that not all mathematical concepts correspond to physical phenomena. But when correspondences are found, the physicist can forget about observation and focus on math alone.
the way we tend to realize something may possibly be a universal in most cases is through induction (note: I'm not claiming all cases). After we conclude "P maybe generalized to a universal" we then seek deductive justification for that generalization.
There is a third possibility you failed to consider. You can tell something is a fact because you deduced it from other known facts, you can tell that something seems to be true because it looks like different versions of the same fact (induction), or you can tell that something is a fact because it is the consequence of a definition. The latter case can never be proved wrong and is independent of observation.
Consider this definition of gender: "humans can be divided in two gender: male and female. Females can give birth, males cannot". That definition has a few consequences. For instance, you can be sure there is no species whose male can give birth. You can also be sure that a species will become extinct if all females die. You can suspect some species do not have males. You can learn quite a lot of very solid knowledge about the world simply by coming up with good definitions, in which case you only have to deal with definition and deduction, and completely ignore induction and its problems.
Now to the last...
kant said:
Utimately, we can only test the existence of something based on it ` s effect on something else.
I like that. It means something exist if it is capable of interaction. It's a good definition. It also implies nothing can exist by itself. (homework assignment: can the universe exist if it has, by definition, nothing to interact with?)
The height of a shadow might not indicated the existence of the shadow, but it can indicate the existence of some other things.
Surely the perception of a shadow is proof that something causing your perception exists. My point was only that it may be misleading to think it's the shadow itself that is giving you the perception. In your terms, the shadow can be said not to exist because it doesn't interact with you, it's ambient light and the wal that are doing that.
I agree. You can say the universe correspond to a set S, and that everything in the set exist. But what is that got to do with physical existence? Can you create another space-time universe by write down math equations, and say it "exist"?
Actually, you can. Whether you can relate the universe you made up in your mind with something real, that is the job for the scientist in you.
If a person was to be born inside a dark room, and all he has is his brain. Can we deduce modern physics by knowing peano axioms? Obvious not.
Not so fast! To start with, wouldn't that person's brain behave according to the laws of physics? If so, couldn't that brain discover physics simply by examining itself? Moreover, how can we be sure that physics is not, in fact, simply describing the behavior of our "brains" rather than the world?
(don't answer, just think about it)
Physicists use mathematics as a tool, but it is not true that mathematician uses empirical facts to deduce theorms in number theory
That was not the point. The point is that no empirical fact ever proved a mathematical theorem wrong. The only reason mathematicians don't conduct experiments is simply because they don't need them. They could if they wanted, just like you can count pebbles to check the correctness of your calculations.
The statement "1+2=3" is analytically true, but by itself it tells us nothing about the physical universe, unless we assign numbers with applies. Can "1+2=3" tell use why applies exist?
No, but it tells us why you get three apples when you put one on a table and somebody else adds two.
Besides, ultimately there must be something which exists for no reason. Apples exist because of apple trees, and trees because of seeds and soil and sunlight and photosynthesis, and so on and on. You go on with that but eventually you must reach a point whence you can go on no more.
Stephen hawking said some like this. He said even if we have a set of equation that describe everything in the universe. It could only be a set of equations. He asked: " what breath fire into the equations in the first place to make a universe from it?". What hawking means is that science cannot tell us why there is something for our equations to describe.
I don't think Hawking is a particularly good philosopher (nor should he be). He sees the laws of physics as some sort of computer program, so it is natural for him to ask "where is the computer running the program?". There are better ways of seeing things that don't lead to such naïve questions.
(man, I'm exhausted!)
Physicists use mathematics as a tool, but it is not true that mathematician uses empirical facts to deduce theorms in number theory.