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Physics, Astronomy & Cosmology / Do bodies decay where life doesn't exist

« on: 17/07/2009 03:12:31 »

I'm not sure if this is the right forum for this, but my question is if a human body (or really any body) were placed out in space or on the surface of Mars (assuming there's no life around), would it still decay? If it does, what would cause it?

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Physics, Astronomy & Cosmology / Can your blood boil in the vacuum of space if you have a cut on your arm?

« on: 11/05/2009 22:45:23 »

** Minor Spoiler alert for those that haven't seen the new Star Trek movie **

I was reading an article on Bad Astronomy about the science in the new Star Trek movie, and one of the scenes that was mentioned was when Bones was concerned their transporter might crack and they'd be exposed to space where your blood would boil. BA mentioned that it wouldn't happen because your blood is sealed up in your body, which is air tight. But what if you had a cut on your arm that was exposing your blood? Would it boil and would it cause the rest of your blood in your body to boil?

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Physics, Astronomy & Cosmology / Can the Human Mind Affect Atomic or Quantum Particles?

« on: 15/04/2009 23:51:45 »

The basic question is can the human mind control or affect the movement of atomic or quantum particles? I remember seeing a show on the Science Channel or Discovery about an experiment that someone did using water. He gave a person a bowl of water or a tray of water and had them think happy, sad, angry, depressed thoughts while the water was being frozen. Then looking at the ice crystals of the water through a microscope, they found that the water molecules were arranged differently based on the "thoughts" that the person projected at the water.

To me that seems kinda far-fetched, and I'm sure water isn't going to freeze in the exact same way everytime regardless what thoughts are being "projected" upon it, but it got me thinking. I remember reading an article about observing quantum particles and that the very act of observing a particle causes it to affect its reality...that particles behave differently when not observing them. So this raises my question, are our minds able to control these particles? And if so, would it then make sense that with enough skill we could manipulate atoms and even multiple atoms where we could eventually be able to move physical objects with our minds? What about creating or destroying particles?

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General Science / Could a coin really land tail-side up 1000 times in a row?

« on: 05/08/2008 17:20:43 »

Sorry for the confusion. It was rather late at night. I should explain myself a bit better as I certainly didn't mean to offend anyone, if I did.

I guess what I am getting at is based on an argument between a friend and myself. She believes that life, matter, and reality all occurred by pure chance, while I do not. My argument was that in order for life to just occur would involve a lot of precise events all happening at the right time and space to produce life. Since neither of us knew what the actual probability of that happening, I equated it to being similar to tossing a coin thousands of times and having it land tail every time. Or shuffling a deck of cards and having the result being a completed ordered deck.

Her rebuttal was simple: Probability shows that there IS a chance of that happening although minute. But this seems like a leap of faith to me and made me actually question the use of math in that fashion. Of course, I'd be taking a leap of faith as well if I say that life was created by a higher power.

I remember reading somewhere that Einstein or Hawkings predicted that time travel could be possible using a mathematical formula as it relates to gravitational fields near a black hole. And I recall reading other science articles about a variety of predictions based off a math equation. I certainly don't mean that they are wrong because math is not concrete proof, but it did make me wonder just how valid it is to use math to predict or prove things in science.

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General Science / Could a coin really land tail-side up 1000 times in a row?

« on: 05/08/2008 07:35:51 »

I know this isn't a math forum, but I've been thinking about how math works (or doesn't work) in reality. For example, math states that there is a possibility that I can flip a coin a thousand, or even a million times and have the coin land tails every time (assuming that the coin and flipper are NOT in a perfectly controlled and finely tuned environment where physics would cause the coin to land on tail every time). But is it REALLY possible to have this kind of outcome in reality? Does this mean that using math to predict something in science is invalid?

[mod edit - subject reformatted as a question - please try to do this in future as it helps other forum users to find information and relevant posts more quickly.]

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Physics, Astronomy & Cosmology / How can Black Holes Vary in Size?

« on: 21/05/2008 20:58:58 »

Assuming that black holes contain a singularity in its center, I'm confused as to how black holes can vary in size. The singularity is a point of infinite density (and gravity) compressed into zero volume, right? If so, wouldn't that mean that all singularities would technically have to be the exact same "size"? And if they are the same "size", then the sphere of gravitational influence also has to be the same "size"?

It all seems a bit strange to me...wouldn't it make more sense if black holes really weren't "holes", but just incredibly large objects (in terms of mass) that have enough gravity to keep light from escaping? This way we don't have the laws of physics break/fail, and would help explain why black "holes" can be supermassive or extremely tiny enough to be created in a particle accelerator.

Am I way off on this?

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Physics, Astronomy & Cosmology / Re: Massless Existence

« on: 14/12/2006 01:55:40 »

Excellent! Thank you Helio. I understand now

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Physics, Astronomy & Cosmology / Re: Massless Existence

« on: 13/12/2006 19:24:27 »

I figure that in order to be able to physically touch something or alter it, it would have to have mass. I mean, we can't destroy gravity or time nor can we manipulate it (not to my knowledge anyways). I can't think of any massless "object" that can be destroyed.

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Physics, Astronomy & Cosmology / Re: Massless Existence

« on: 13/12/2006 01:34:37 »

I'm confused. How can you destroy something that has no mass?

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Physics, Astronomy & Cosmology / Massless Existence

« on: 12/12/2006 22:22:53 »

If I remember correctly, some people say that light/photons are massless, and that they travel so fast because it would otherwise take an infinite amount of energy to move at that speed if photons did have even a tiny mass. So this got me thinking about other massless "things" such as gravity, time, and the thoughts in my mind. Even though we can't physically SEE gravity, we can see its effects such as the apple falling to the ground...and we can't see the thoughts in someone's head, but we can see the effects of people's decisions.

But light...if light really is massless, we shouldn't be able to see it, so what effect from the photons are we seeing that causes "light"? I figured it would be friction as the photons rip through space, but then we'd also experience a great deal of heat too, right? And if the photon is massless, how could it even cause friction in the first place? So what exactly is the "light" that we are seeing? Or am I looking at this totally wrong? Thanks!

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Physics, Astronomy & Cosmology / Having Trouble with Time and Space

« on: 16/11/2006 22:40:52 »

I don't understand how Time dilates when moving at extremely fast speeds and hoping someone can give me some insight. Take the Twin Paradox for example...how is it that the twin that's traveling at 60% of lightspeed ages slower than his counterpart? I'm sure I'm not thinking of it in the correct way, but wouldn't that mean that if I could travel at the speed of light that I'd never age? I'd live forever?

To me, it seems that this Paradox is assuming that Time and Space are the same. Here's the way I'm looking at this, and please help me understand if I'm wrong:

Let's suppose there's a star 5 light years away from Earth that has died and became a Supernova. Obviously, from Earth the star still appears in the nightsky and we won't see the supernova for another 5 years. If I begin traveling towards this star at the speed of light, I'll notice 2 things:

1) Time will appear to speed up as I'm looking forward, correct? This is because I'm moving headon into light from that star that is heading towards me at the speed of light...so I'll notice events happening faster. By the time I reach the light of the star turning into a supernova, I will see the supernova happening at something like 2x speed.
2) Time will appear to stop or slow down as I look behind me. This is because I'm traveling at the same speed as the light heading in the same direction. If I were to travel faster than light, then it would appear that Time is reversing, yes?

But none of this means that Time did indeed get manipulated. It's all an optical illusion.

Now, let's suppose 5 years of travel and I reach the star (now a supernova). If I look at the Earth from here, I'll be looking at an image of Earth that is 5 years old. My Twin on Earth will look exactly as he did the day I left Earth, even though he is 5 years older now. Essentially, I am looking at a representation of the past because light doesn't move instantaneously. If I were to instantaneously travel back to Earth...my Twin would be 5 years older than what I observed from the Supernova site. And I would be 5 years older than when I left Earth. But we'd still be the same age to my understanding...assuming that Time and Space are separate entities/dimensions.

So where am I wrong in all this?

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Physics, Astronomy & Cosmology / Re: The Concept of Time

« on: 18/03/2006 19:10:29 »

quote:Originally posted by Soul Surfer

Time is what stops everything happening at once.  Read Julian Barbour "The end of time" if you want to get really confused or maybe a bit more insight.

Thanks! I'll check it out. I like being confused

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Physics, Astronomy & Cosmology / Re: The Concept of Time

« on: 18/03/2006 19:09:37 »

quote:Originally posted by average guy

Space is 3 dimensional.

There is no such thing as time, just motion.

If you stopped the universe and reversed the direction of everything I do not think we would go back in "time".

What happens if we are able to reverse motion...would there be a beginning? If we could speed up motion, would there be an end? If Time really is just the measurement of motion, this would make "time travel" a pretty daunting task...because you'll need to simultaneously alter the motion of EVERY single atom in the entire Universe.

Would this alteration affect memory? If we reverse motion and then move it forward, would our memories ALSO move backwards? IF so, "Time travel" would be useless, since we wouldn't KNOW or remember that we did it. And therefore could not produce any paradoxes because we'd be forced to move forward in the exact way before we moved back. There'd be no way for us to purposely change the "future" motion. And so perhaps, life is predestined and Free Will doesn't exist.

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Physics, Astronomy & Cosmology / The Concept of Time

« on: 17/03/2006 04:15:52 »

Time is a bizarre concept, and that intrigues me, especially what happened BEFORE time. Can there be such a thing as "before time"? Some people believe that the Big Bang was the very moment that our Universe was brought into existence. But what happened before that? And how long was there a "nothing"? Did Time not even exist at that point? But if that's the case, then how could anything exist? I think there are really only 3 possible answers to these questions:

1) The Universe and Time simply always existed, created by God who also always existed. Personally, I find this answer a cop out.

2) Just before the Big Bang, the entire mass of the Universe was a point of infinite density, like a singularity. And there simply was no Time before that point because the Universe in this state is dimensionless and the infinite gravity warps Spacetime greatly.

3) Time is infinite and has no beginning or end. In this model, if we had the ability to travel backwards in time, we would travel backwards for an infinite amount of "time" and never get to a beginning. This is a hard idea for me to accept, because how could anything have been? There has to be a beginning of Time, yes? It's cause and effect. I exist because my parents created me who exist because their parents created them and on and on. I mean, how does Time or anything exist without something to CAUSE it to exist, which implies that at some point, it didn't exist.

Maybe I'm thinking of Time as linear. What if Time were spherical - a circle that doesn't have a beginning or an end? But in this model, if we travel back in time far enough, we'll eventually reach the future and then back to the time where we started our journey. And perhaps the Big Bang is that point of the circle where the past and the future meet - the point of repetition.

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Physics, Astronomy & Cosmology / Re: Burning Up in the Atmosphere

« on: 14/03/2006 18:10:35 »

Haha...very nice. Thanks guys

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Physics, Astronomy & Cosmology / Burning Up in the Atmosphere

« on: 14/03/2006 02:39:59 »

What exactly causes objects to burn up in our atmosphere? Is it simply friction, and that faster moving objects get hotter quicker? Or does the atmosphere function like a sort of magnifying glass and causes the sun's ray to superheat? I never hear of rockets leaving the Earth's atmosphere experiencing any sort of "burn" as they enter space...but perhaps I'm not educated enough

Is it possible to ascend to Earth from space in a way that won't cause a "burn out" entering the atmosphere? Is it possible to extend a pole, wire, string, etc from the Earth and attach it to the Space Station or something else out in orbit?

I know I'm asking a lot of questions...just not having much luck finding any useful answers via Google and the curiousity is haunting me.

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General Science / Daydreaming and Reality

« on: 07/03/2006 16:33:52 »

I remember driving home one afternoon, and for some reason started daydreaming about my plans for the evening. Perhaps it's my ADD that does this, but my daydream essentially turned into a mini-movie, where I was dreaming about going out with my friends at a bar and meeting a cute girl there and all the things that I'd say to her...and start over if I didn't like the outcome. All of this happens within seconds in my mind.

And it's about this time that I snap back into "reality" having realized that I was daydreaming while driving. I know I was aware that I was driving the entire time, but wasn't paying attention to what I was doing. I was running on a sort of auto-pilot.

I remember reading somewhere that the human brain can handle only so many signals it receives (1000?) at one time, and so I wonder where daydreaming fits into this. I'm kind of curious to wonder how many signals my brain is receiving just from daydreaming, and is it really that many that it causes me to not pay attention in reality? Having ADD, does this mean my brain can't handle as many signals as non-ADD people can?

I have been able to get so deep into a daydream that I can feel the effects of it as if it were reality. For example, if I'm daydreaming about riding a rollercoaster and I'm REALLY into it...I can actually feel my stomach churn and my head swim as if I really was riding the rollercoaster. A lot of the times, it's intense enough where it'll jar me "awake" and I notice my heart beating fast because of the adrenaline.

Does anyone else have this problem? What is it exactly? And am I'm slowly going insane?

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General Science / Re: Space time

« on: 02/03/2006 05:05:22 »

Think of "spacetime" as an extremely elastic piece of paper. By itself, it's flat and straight. But add some weight (aka a planet), and the paper bends where the weigh is. THAT is the bending of spacetime. Lame analogy, I know...but hopefully it explains the idea

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General Science / Re: To Control Every Aspect of One's Self

« on: 26/02/2006 20:33:03 »

So perhaps, because of the intricate way our bodies behave with us needing full control...I wonder if this points to the fact that we have been "created" by a higher power.

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General Science / To Control Every Aspect of One's Self

« on: 26/02/2006 06:29:43 »

Obviously, most people have the ability to control certain aspects of their own body - moving your arm, unfocusing your eyes, breathing. Simple things that we do everyday. But there are so many parts of our OWN body that we cannot control, or maybe don't know how to control. For example, can you stop your fingernails from growing? Can you increase your heartrate on the spot? Can you make your stomach stop digesting food? Can you turn on or off any range of emotion at any time?

Perhaps there ARE people that can do some of these things, and I would think that it makes sense that you should be able to control your body. I mean, I can stop breathing if I want to, but I can't just stop my heart (Not that I want to!).

I'm not sure where I'm going with this other than I wonder why we can control certain parts of our bodies and not others. Is there a particular reason? Is it simply a lack of practice?

-Xin