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We don't know how the universe began, and we will never know

backreaction.blogspot.com

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Re: We don't know how the universe began, and we will never know

#381

This is what I don't get: "... if the universe expands today, this means if we look back in time the matter must have been squeezed together, so the density was higher. If the universe expands today, how does it follow that it was also expanding yesterday, or a million years ago? Maybe universe expands, then contracts again cyclically?

> Maybe universe expands, then contracts again cyclically?

It's possible, but you're going to have to come up with a theory for why whatever 'force' is driving the expansion goes from negative, to positive, and back.

Re: We don't know how the universe began, and we will never know

#382

This is what I don't get: "... if the universe expands today, this means if we look back in time the matter must have been squeezed together, so the density was higher. If the universe expands today, how does it follow that it was also expanding yesterday, or a million years ago? Maybe universe expands, then contracts again cyclically?

The reason expansion yesterday is plausible if we see expansion is simply that's it's far more plausible nothing so special happened yesterday as to change the motion of the entire universe.

The universe is not a little trickle of water down the wall in the bathroom you can easily redirect with your little finger, the universe it really big, so you need something equally big to make it change behaviour.

Re: We don't know how the universe began, and we will never know

#383
post #381

This is what I don't get: "... if the universe expands today, this means if we look back in time the matter must have been squeezed together, so the density was higher. If the universe expands today, how does it follow that it was also expanding yesterday, or a million years ago? Maybe universe expands, then contracts again cyclically?

> Maybe universe expands, then contracts again cyclically? It's possible, but you're going to have to come up with a theory for why whatever 'force' is driving the expansion goes from negative, to positive, and back.

We live inside an engine piston?

Re: We don't know how the universe began, and we will never know

#384

Earlier quoted context omitted.

> Faith by definition isn't something which can be backed by evidence There is evidence backed belief in the unseen, and there is blind faith. So your claim that by definition faith is without evidence is not correct. Secondly, even science needs to accept certain axioms as a given so that we can build upon them. Scientism is believing that the only way to arrive at truth is through experimentation, which is a false…

It took him 8 minutes to actually set himself up to actually start talking and the first thing that came out of Dr Ali's mouth is a lie. He said of 4 prominent authors promoting atheism that he described as the four horsemen of atheism that their primary argument is that god isn't good ergo god isn't real. This...just isn't true. It's a gross reduction. I'm 8 minutes in and your speaker's only substantial point is a…

> He said of 4 prominent authors promoting atheism that he described as the four horsemen of atheism that their primary argument is that god isn't good ergo god isn't real. This...just isn't true.

How is it a lie? It's a summary, sure, he can only go into so much given the time. He shows a book by one of them and the title is a giveaway of that summary.

> false rant about Islam being inherently peaceful

Based on what are you claiming that it is false? If you confusing peaceful with pacifist, then Islam is not pacifist.

> nor promote what we would today think of as peace

Then inform us what we would today think of as peace.

> It is common to mistake change in social norms as decay instead of progression

It's easy to see the social decay over time. Of course each generation is experiencing such a decay when they compare it to the previous generations, but we clearly see how things are speeding up. Just look at the ills that we see in so called "developed first world nations", the mental illnesses, the decline of morals, the normalization and over sexualization of behaviors, all the way to children, the destruction of the extended family, then the nuclear family. It's quite obvious where things are heading. This is not fear mongering. When you have someone like Kraus saying that he cannot find a moral argument against incest, then someone with half a brain should think about what this means.

> Your speaker declares that a fiction is the root of all morality

I'm not sure where he said that.

> Trying to apply this moralistically towards human beings is both a misunderstanding of humanity, ethics, and science.

No it isn't. From a purely secular and atheistic world view, there was nothing wrong or bad about horrific historic events like the Holocaust, the nuclear bombs, rape, Epstein, etc. I think it was one of those "four horsemen" who said that rape is not good or bad, but it's just a phenomenon like the spots on a cheetah. Even this atheist biology professor claims that there is no ultimate foundation for ethics from an atheistic world view: https://youtu.be/EqK_JPts26k?t=182

That is the only logical conclusion to arrive at from an atheistic world view, at least he's being honest with himself. More atheists should be honest with themselves as well and we'll see how things end up.

> We don't need Jesus or Allah to tell us this is a bad idea.

Based on the above, we sure do.

> while silence is likely to reign in environments were life is impossible or unlikely.

Yet, we exist. So our world is clearly viable for hosting life. I'm not sure what you're getting at here.

> Likely he has but he hopes you will click a youtube video and sit back and passively absorb re-enforcement of your existing beliefs than actually reading a book yourself.

He's a professor and a scholar of biblical hermeneutics with field specialties in Sacred Languages, Comparative Theology, and Comparative Literature. He doesn't "hope" anything. It seems you're straw manning because you think we in Islam shy away from debates or discussion. That couldn't be further from the truth.

> May I suggest you read something written by one of the "four horsemen" of atheism?

Like the time where Dawkins falsely and cringely claims that Islam teaches that salt water and sweet water don't mix? I've watched lectures for those people, and their arguments are straw men, or just outright lies that shows their ignorance and malice especially when it comes to Islam.

Bear in mind that this lecture was just to have people expand their horizons, especially those that think that science is going to answer everything. It won't. There is so much material out there by good people who have torn down these atheistic arguments. People like Youtube these days, so I recommend Mohammad Hijab and Sami Ameri. I have lots more who speak Arabic, but I think this is not the right audience for them.

Re: We don't know how the universe began, and we will never know

#385

I’m a big fan of the blog, but disagree with this entry. Her argument could be applied to the idea of the Big Bang itself: we can never receive light from any further back than the “surface of last scattering”, so the notion of a hotter prior epoch is an extrapolation. The extrapolation is a good one as it uses independently-tested laws of evolution, at least to the point these laws presumably break down, as she poin…

> Her argument could be applied to the idea of the Big Bang itself What's wrong with that? The thing about science is that it cannot pretend that it knows. It needs to prove. To which end, I don't think we should be supposing that we're going to know. Otherwise we're doing religion.

Science is, effectively, religion/faith in a particular set of base presumptions (axioms of set theory or logic theory guide all "logical" reasoning). Basically, limits of human mind understanding things come with just having to trust some things are simply so.

The biggest difference from things more commonly referred to as "religions" is that science invites you to challenge all these assumptions and look for a better (and smaller, simpler) working set that still explains all the phenomena we observe at least as well as the sets of axioms we currently use. And it knows that all the knowledge we gain is simply the approximation of the real stuff, and that we can only work to improve those approximations.

Re: We don't know how the universe began, and we will never know

#386
post #381

Earlier quoted context omitted.

> Maybe universe expands, then contracts again cyclically? It's possible, but you're going to have to come up with a theory for why whatever 'force' is driving the expansion goes from negative, to positive, and back.

We live inside an engine piston?

And what wheel drives the inner workings of that piston?

Re: We don't know how the universe began, and we will never know

#387

What if it never began and has simply always existed? That is the likely scenario, as the moment you think about it beginning, you again face beginning from what? What was that called before the universe other than the universe?

If the universe is infinitely old - well, what’s the probability that, untold (yet finite) aeons ago, a planet existed just like this one, in which history unfolded in exactly the same way, even the pettiest details of our lives being precisely the same? I think the probability is arbitrarily close to 1 - not just that our lives have happened exactly the same before once, but an arbitrary - even infinite - number of…

Well, there's also the possibility that the universe occupied some single state (say, the singularity posited by the big bang theory) since t=-inf to some t0 when it exploded, and that the dynamical laws are of such a nature that it can never return to that state.

Right now, the prevailing model of cosmology (lambda-CDM) basically says that the universe can never return to an earlier state, as it is constantly expanding (and that expansion is accelerating). In this model, the universe has an infinite number of possible states, and is in fact guaranteed to never visit a previous state, even though it has an infinite future ahead of it.

Re: We don't know how the universe began, and we will never know

#388

This is what I don't get: "... if the universe expands today, this means if we look back in time the matter must have been squeezed together, so the density was higher. If the universe expands today, how does it follow that it was also expanding yesterday, or a million years ago? Maybe universe expands, then contracts again cyclically?

No post body was provided.

Re: We don't know how the universe began, and we will never know

#389

This is what I don't get: "... if the universe expands today, this means if we look back in time the matter must have been squeezed together, so the density was higher. If the universe expands today, how does it follow that it was also expanding yesterday, or a million years ago? Maybe universe expands, then contracts again cyclically?

> If the universe expands today, how does it follow that it was also expanding yesterday

The universe is not only expanding, it's expanding faster and faster... it's very hard to see how anything could explain the rate of expansion could have started off negative, then instead of just collapsing into itself, it reverted somehow and then started accelerating. The simple explanation is that it has always expanded, though at a slower rate, just like in the future it seems it will continue to expand at a faster rate.

Re: We don't know how the universe began, and we will never know

#390

I’m a big fan of the blog, but disagree with this entry. Her argument could be applied to the idea of the Big Bang itself: we can never receive light from any further back than the “surface of last scattering”, so the notion of a hotter prior epoch is an extrapolation. The extrapolation is a good one as it uses independently-tested laws of evolution, at least to the point these laws presumably break down, as she poin…

> Similarly, it’s entirely conceivable that we may find independent ways to test which of the proposed modifications of the evolution laws is correct, for instance by using data collected from binary mergers. Then, these modified laws would lead to a modified story of what happened near the Big Bang. Sure, but you have to start from observations of the binary merger, not from what you'd like the Big Bang to be like,…

Einstein's equations are time reservable and deterministic, so the evolution has only one path and ultimately it doesn't matter which end you start at, you'll get to the other unique end point regardless. The problem is to get the correct start conditions that makes the other end of the path end up somewhere plausible.

It is largely a matter of training and temperament if you think it's more rewarding to start from the observations of current phenomena that all have some uncertainty and laboriously work backwards to predict an early universe that doesn't match the observations and then have to start over, or if you think it's better to start from the distant past and work toward the now only to find a problem and having to start over.

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