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Physiology & Medicine / Why is life so delicate in regards to temperature?

« on: 22/07/2016 20:23:30 »

I've always wondered this... How the temperature range found in the universe is so immense, from just above absolute zero to trillions of degrees celsius; yet life will generally only thrive in what, like a 200 degree range?  That's like .0000000028 of a %.  That's kinda insane to think about right? 

But why, if atoms can obviously handle such an incredibly large range of temperatures, would life, which is nothing but a collection of atoms at the end of the day, be so delicate, to only be able to handle .0000000028 of a % of the universal range?

Kinda a weird question, but just a curiosity.

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Physics, Astronomy & Cosmology / How come stars won't form if the dust cloud is too hot?

« on: 20/07/2016 22:59:46 »

I was reading an article yesterday about their having found some evidence to support the direct collapse theory; that dust clouds directly collapsed to form supermassive black holes prior to galaxy formation etc.  And one thing the piqued my interest in the article was it saying that the temperature was so hot that the hydrogen and helium couldn't collapse into stars, but instead directly collapsed into black holes.  But I thought the heat generated by gravity and the particles bumping into each other or whatever is how stars collapse to start the fusion process to begin with?  So why wouldn't this occur if things were too hot?? 

My apologies if a stupid question.  But definitely something I hadn't prior known.

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Physics, Astronomy & Cosmology / Why is it called dark matter instead of dark gravity?

« on: 08/07/2016 17:31:21 »

Hi all!

As is the case with many lovers of Physics, dark matter and dark energy fascinate me. I think about them often, trying to wrap my head around them.

But I'm curious about something with dark matter I'm hoping some of you can shed light on.  What makes the scientific community convinced it's matter at all? 

I understand the calculations, the speed of stars around galaxies, I understand why DM needed to be added etc.  And I want it known that none of the questions or theoretical things I'm asking are meant to come off as new theory etc.  I'm just asking the proceeding questions to get a real solid answer rooted in physics and fact, just to help me understand.  I just wanted to give that caveat.

But my question is having that said, understanding the calculations and why the extra gravity is apparent, why must it be a new form of undetectable matter that has no interaction electromagnetically to be the culprit?  Why isn't it called dark gravity instead, merely gravity that we know is present but we don't understand why?  Why must some mystery, as of yet undetected, made of different stuff than we can fathom particle be the solution?  I guess that part just confuses me.  Why the focus on this unimaginable particle instead of a focus on what other things might cause gravity itself to increase without the need for a mass to be present?

For example, we know that spacetime can curve, and that this curvature is directly related to gravity.  Is it not possible that other things we haven't yet thought of can also create this curvature?  I know for example there is strong belief (shown through the microwave background) that dark matter existed first and was the scaffolding that baryonic matter attached itself to in order to form galaxies etc.  We also know the energy that was released in the big bang, and the expansion that took place thereafter.  During this time when physics might not have even existed yet, couldn't that scaffolding have been something like the energy being so hot and dense, so different than anything we can relate to, that as the singularity expanded and spacetime came into being that these were just permanent curves in that spacetime brought on by that energy, almost like flaws, cracks, or another analogy, that kinda were always there and just expanded with spacetime from the start?  And then because of this inherent gravity, this permanent scarring or curvature, real atoms gravitated towards those areas and ultimately formed galaxies etc?

And again, I'm not putting forth a new theory, cause it's totally based on ignorance (my lack of knowing).  It's just I guess one of my mental examples that makes me want to not be as ignorant on the subject, to understand it more.  I guess the main question is why instead of being focused on gravity itself, what else might cause spacetime to curve, that could be attributed to what we see when we measure the speed of galaxies etc and find they don't have enough gravity from ordinary matter to keep them together, do we instead focus on a new form of matter altogether to be responsible?

So summed up, why dark matter instead of merely dark gravity?

And I ask with sincerity.  I'm fascinated with the concept and wanna learn more about it, so that I can think more deeply about it but rooted in as much fact as possible.

Thanks in advance!

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Physics, Astronomy & Cosmology / At A Subatomic Scale Could We Tell Where Any Given Object Ends & Another Begins?

« on: 20/06/2016 17:17:59 »

Every night when I got to bed I think deeply about all sorts of stuff dealing with our universe, and I'll do thought experiments, or theorize about black holes, or the big bang, or gravity, or time... I'll think about the sheer scale of the universe, and imagine peering down upon it etc.  But last night I went the other direction.  I imagined what I'm made of, thinking about all the space between my atoms, what if I was to zoom in, and keep zooming in, I would look like; if I was say in a sub atomic spaceship flying around within me.

But then I was fascinated by something...  When it comes down to it, every particle I'm made of, and in fact, every particle that everything that is anything generally is made of, is made up of up quarks and down quarks.  So that made me think further... That if I was flying around within me, and I could see to such a small scale; suspending for a minute the fact that there would be so much space in between every particle I came across, what I would be seeing is a soup of up quarks and down quarks, no real distinction between them.  Just these elementary particles with a bunch of space and electromagnetic interactions between them.  But what that also means, is that I would never, ever be able to tell when my spaceship crossed from 'me' and into the bed, or from the bed into the floor etc.  It would all just look exactly the same.

In fact, this entire universe, if looked at from above as a whole, but able to be zoomed in to that level, would just be a bunch of quarks, with no distinct anything.  All of us would be identical, but not just to each other, but even to the chair I'm sitting in right now.  We want to consider ourselves to be special, to be sentient, and different than the rock we pick up and throw.  But are we?  Even our consciousness is just the product of these quarks (as well as from electrons and electromagnetic interactions etc), everything we are is.   So when it comes down to it, I am no different from this chair.  At all. In any way whatsoever.  Our particles are exactly the same, to where if I was flying that ship, I would never, ever be able to tell when I had left my physical body and ventured into the chair instead.   No matter what substance each was made from, no matter what molecules, how many protons, how many neutrons, when considering the space that would be between them all, it would just be a bunch of floating quarks indistinguishable from one form of matter to the next.

This concept fascinated me, this thought that I am my chair, and it me. That all matter shares this common bond, that it is all the same, made of just two different types of quarks.  And that no matter how deeply I think, I am no more special than any of it.  My quarks are just simply in different orientations and are having different interactions.  But we're all still just these quarks, same as our chairs.  So now when I talk to inanimate objects, I won't feel as crazy.

But am I missing something here, or at a simplistic level, is this correct?  If just flying throughout this soup of quarks, would an observer ever be able to tell where my body ended and my chair begins?