Science stuff that blew your mind when you first heard of it

[Xanadu84]

It may be more math then science, but Benfords Law/ Dear lord, the term, "Hurts my brain" is usually a metaphor.

http://en.wikipedia.org/wiki/Benford's_law

Here's the long and the short of it. If you take a set of numbers, MOST sets of numbers, you can look at the first number. So 1, 107, 1973, 1.9 and the like all begin with "1". Take, for example, the 60 largest structures in the world. Look at their heights. About 30% of those number will begin with the number 1. About 5% will begin with 9, and the frequencies of numbers in between change accordingly. So odds are very good that if you take a random tall building, its height will be be a number that begind with 1. Weird right?

No, not yet.

Take those same building heights, and this rule applies IN OTHER SYSTEMS OF MEASUREMENT. Even though the measured height in Feet might begin with 1, and the height in Meters may begin with 9, when you look at all the heights together, 30% of those numbers will begin with 1, and about 5% will begin with 9. So now its as weird as it gets rightg?

Nope.

This rule applies IN OTHER BASE SYSTEMS. So whether you measure a bunch of towers in base 10 feet, and again in base 6 meters, most of the measurements will begin with 1. Needless to say the percentages are different, but seemingly random numbers tend to begin with smaller integers. Mind blown yet? No? Well...

This law can be used with remarkable accuracy by forensic accountants to discover fraud. Essentially, when a person committing fraud picks random numbers, a forensic accountant can figure out that it is fraud by realizing that there is not a strong preference for numbers that begin with 1.

It's weird until you think about it, and then it is TERRIFYING.

 

[BrassButtons]

Snip

>.< I work with numbers. You know I'm going to be seeing this ALL DAY now, right? I hope you're happy.

 

[Mazza35]

The fact that we never touch anything. Ever.

Sciencey part: We all know that positive and negative repulse each other yes? So if I got a single hydrogen atom, which is JUST a Proton (+) and an electron (-) and tried to push it to another H-atom, they will never touch under normal day to day circumstances (Barring Nuclear Fusion, which is awesome) got this so far? Sure different and even the same atoms can BOND, which is just chilling VERY VERY close to each other, not forming another atom. But, if I went to move a chair, the atoms in my hand and the atoms within the chair, would not actually touch, they would just come really really close together and repulse at a aubatomic level. Im horrible at explaining this, so science people can do a better job:

http://www.youtube.com/watch?v=OBZr1qmsQ0U

 

[Adventurer2626]

That the mantle is not so much liquid as playdough/plastic. (Disapproving glare at public high school education) Someone recently found a better way to make steel. That we're already harvesting asteroids. Diamonds aren't that rare, they're just being held for ransom. Magnets. Nothing is independent or isolated; everything affects everything. The sophistication of plant hormones to regenerate and adapt to environmental changes. There's quite a bit, that's just all that I can think of.

 

[BlackStar42]

In space, the low pressure will cause water to boil. The human body is mostly water. If you were exposed to vacuum, the water in your eyes would boil away, your blood would start boiling, air would leave your body through every available orifice causing you to shit, piss and vomit simultaneously while sucking all the air from your lungs. In short- not recommended.

What amazes me? Quantum mechanics. Especially the fact that an electron can travel from one space to another without moving through the space in between.

 

[dvd_72]

That space and time probably have indivisible units. that's right people, space is grainy and you can actually find the frame rate of all existence! Then again this was a little while ago, in some articles, so I haven't really gone that far into it.

 

[dvd_72]

One thing that I found fascinating...

You can walk in space without a suit and live.

You'd think it would be very cold in space, but it isn't, that is to say, not as cold as some of the coldest places on Earth.

There's nothing in space, ergo, nothing to take heat away from your body. So you can, in theory, hold you breath and walk in space for a few moments, unscathed.

[sub]I heard this somewhere, so if I'm wrong, do tell me.[/sub]

I'm fairly certain that temperature is the measure of the average kinetic energy of particles in an area, if then there is an area with no particles (ie space) there is no kinetic energy and therefore the temperature is absolute 0. Far colder than anywhere on earth I assure you

OT: The idea that space and time are linked makes my head hurt

While true, vacuum has no temperature. A particle is the thing that has the "heat" that is the temperature we measure. Now, because space has very few particles at low temperatures to take heat away from the body the only way for the body to loose heat would be by radiation, which as mentioned before is a very slow process. Vacuum is, after all, the best insulator out there! Chances are you'd probably start to feel warm as the natural loss of energy through conduction and convection are no longer present, causing the heat normally lost through there to build up. Eventually it would reach an equilibrium point where you're hot enough to radiate as much energy as your body produces.

 

[Jonluw]

Quantum Entanglement.

By the time I heard of it, I was well familiar with the SOL limit on both energy and mass. Then I discover that certain paired particles are capable of "communicating" instantaneously, over any arbitrary distance

This.
Also, the double slit experiment. Matter is waves? I don't even...

And this:

This STM image shows the direct observation of standing-wave patterns in the local density of states of the Cu(111) surface. These spatial oscillations are quantum-mechanical interference patterns caused by scattering of the two-dimensional electron gas off the Fe adatoms and point defects.

That's a ring of iron atoms under a Scanning tunneling microscope. They did not place an iron atom in the middle of that ring.

 

[Scarim Coral]

Non-contact heating-
How the hell is that ice cube heating up while not melting at all??

 

[antidonkey]

My mind was recently blown by super fluids. Very trippy how you can't really contain them. I don't have the time to find the video but I'm sure there's a few on youtube. Investigate the awesome!

 

[Quaxar]

One thing that I found fascinating...

You can walk in space without a suit and live.

You'd think it would be very cold in space, but it isn't, that is to say, not as cold as some of the coldest places on Earth.

There's nothing in space, ergo, nothing to take heat away from your body. So you can, in theory, hold you breath and walk in space for a few moments, unscathed.

[sub]I heard this somewhere, so if I'm wrong, do tell me.[/sub]

I'm fairly certain that temperature is the measure of the average kinetic energy of particles in an area, if then there is an area with no particles (ie space) there is no kinetic energy and therefore the temperature is absolute 0. Far colder than anywhere on earth I assure you

Actually, due to the Heisenberg uncertainty 0K (&#8722;273.15°C) can only ever exist in theory because if a particle had no energy and therefor no movement it would mean that we could measure it's precise position AND energy. Also, due to gas law (<url=http://en.wikipedia.org/wiki/Charles%27s_law>Charles' law) that links volume and temperature, any gas at 0K would mathematically also have zero volume.
Due to leftover background radiation from the big bang and all that, space is actually <url=http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980301b.html>2,7K or -270,45°C while on earth we've reached about -273°C in artificial cooling experiments. So technically, we've had cooler places on earth although only relevant if you're an atom with a dislike for cold.
EDIT: After a bit of research I want to correct my cooling temperature statement. Turns out the best current example is Yale University, who have cooled a batch of one million fluoromethane molecules down to <url=http://physicsworld.com/cws/article/news/2012/nov/15/millikelvin-cooling-of-large-molecules-is-no-myth>30mK.

 

[XMark]

A few years ago I read a science magazine article (I forget which magazine) about how astronomers were measuring the expansion of the universe. I read about the most prominent current theory being that the expansion of the universe was accelerating. Then I thought of the far future of the universe, of other galaxies expanding beyond the observable universe, of all the stars eventually burning out and nothing but black holes remaining, and then those black holes eventually dissipating, and an eternity of empty darkness.

I also happened to be going through a period of doubting my religion at the time, so my loss of my previous religious beliefs, followed immediately by scientific observation that universe is probably doomed to eternal darkness ended up putting me into a pretty bad depression for about a year.

 

[Redingold]

Actually, due to the Heisenberg uncertainty 0K (&#8722;273.15°C) can only ever exist in theory because if a particle had no energy and therefor no movement it would mean that we could measure it's precise position AND energy. Also, due to gas law (<url=http://en.wikipedia.org/wiki/Charles%27s_law>Charles' law) that links volume and temperature, any gas at 0K would mathematically also have zero volume.
Due to leftover background radiation from the big bang and all that, space is actually <url=http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980301b.html>2,7K or -270,45°C while on earth we've reached about -273°C in artificial cooling experiments. So technically, we've had cooler places on earth although only relevant if you're an atom with a dislike for cold.
EDIT: After a bit of research I want to correct my cooling temperature statement. Turns out the best current example is Yale University, who have cooled a batch of one million fluoromethane molecules down to <url=http://physicsworld.com/cws/article/news/2012/nov/15/millikelvin-cooling-of-large-molecules-is-no-myth>30mK.

That's an abuse of Charles' Law. That law applies to ideal gases, and there's a whole host of assumptions that go with ideal gases that fall apart on a microscopic scale (for instance, the volume of the atoms will prevent the volume from reaching 0, because you can't put two atoms in the same place).

You're also incorrect about Heisenberg. A perfectly stationary particle, with no momentum, would in fact have an infinitely large uncertainty on its position. You couldn't measure its precise position without changing its momentum and making it non-zero. Heisenberg's uncertainty principle is not violated by absolute zero.

EDIT: A team at MIT in 2003 cooled a gas down to about 10[sup]-9[/sup]K.
http://web.mit.edu/newsoffice/2003/cooling.html

 

[FinalHeart95]

Antimatter is essentially matter moving BACKWARDS THROUGH TIME.
WHAT.

 

[Eclectic Dreck]

One thing that I found fascinating...

You can walk in space without a suit and live.

You'd think it would be very cold in space, but it isn't, that is to say, not as cold as some of the coldest places on Earth.

There's nothing in space, ergo, nothing to take heat away from your body. So you can, in theory, hold you breath and walk in space for a few moments, unscathed.

[sub]I heard this somewhere, so if I'm wrong, do tell me.[/sub]

What actually kills you in space quickest is the lack of air pressure. That lack of pressure causes the various gasses in your blood to boil free causing extreme damage in the process. For an explanation of this, skip to about 15:50 in this video:


It isn't an instantaneous process by any stretch but it will certainly cause your death more quickly than heat, cold, or suffocation.

My life with science has been filled with small wonders. Usually the big stuff fails to blow my mind because it takes such a long time to understand that you're comfortable with the notion once you arrive. As for me, I think it was when I first told that the length of a period of a pendulum did not depend upon the arc it carved in space. Or when I accidentally discovered integral calculus in the 9th grade when trying to prove a very stupid point. I didn't know that's what I'd done until I was in college later. I should clarify - I did not discover integration but rather bumped up against the very sort of problem that elicited it's creation in the first place. Of course, my way of getting around it was to actually perform hundreds of recursive calculations thus achieving excellent (but not perfect) accuracy. Had I known that I'd essentially found a Riemann sum at the time (or had anyone else noticed at the time), it would probably have been more formative.

 

[Quaxar]

Actually, due to the Heisenberg uncertainty 0K (&#8722;273.15°C) can only ever exist in theory because if a particle had no energy and therefor no movement it would mean that we could measure it's precise position AND energy. Also, due to gas law (<url=http://en.wikipedia.org/wiki/Charles%27s_law>Charles' law) that links volume and temperature, any gas at 0K would mathematically also have zero volume.
Due to leftover background radiation from the big bang and all that, space is actually <url=http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980301b.html>2,7K or -270,45°C while on earth we've reached about -273°C in artificial cooling experiments. So technically, we've had cooler places on earth although only relevant if you're an atom with a dislike for cold.
EDIT: After a bit of research I want to correct my cooling temperature statement. Turns out the best current example is Yale University, who have cooled a batch of one million fluoromethane molecules down to <url=http://physicsworld.com/cws/article/news/2012/nov/15/millikelvin-cooling-of-large-molecules-is-no-myth>30mK.

That's an abuse of Charles' Law. That law applies to ideal gases, and there's a whole host of assumptions that go with ideal gases that fall apart on a microscopic scale (for instance, the volume of the atoms will prevent the volume from reaching 0, because you can't put two atoms in the same place).

You're also incorrect about Heisenberg. A perfectly stationary particle, with no momentum, would in fact have an infinitely large uncertainty on its position. You couldn't measure its precise position without changing its momentum and making it non-zero. Heisenberg's uncertainty principle is not violated by absolute zero.

EDIT: A team at MIT in 2003 cooled a gas down to about 10[sup]-9[/sup]K.
http://web.mit.edu/newsoffice/2003/cooling.html

Well yes, I said mathematically zero volume, I realize that's not necessarily practical. And it asked for it, didn't you see how provocatively it dressed!?
I was actually going to mention the Third Law of Thermodynamics instead... then I got distracted and I don't know why I changed over to Uncertainty. Still, I maintain that there is some quantum mechanical reason why 0K is unreachable, I just don't remember what the reasoning was.

10-9K? Stupid physicsworld article from November writing like 30mK was some kind of new low! Still, even 30mK is far colder than the coldest known object in the universe, the Boomerang Nebula at 1K, although not as permanent.

 

[Redingold]

Actually, due to the Heisenberg uncertainty 0K (&#8722;273.15°C) can only ever exist in theory because if a particle had no energy and therefor no movement it would mean that we could measure it's precise position AND energy. Also, due to gas law (<url=http://en.wikipedia.org/wiki/Charles%27s_law>Charles' law) that links volume and temperature, any gas at 0K would mathematically also have zero volume.
Due to leftover background radiation from the big bang and all that, space is actually <url=http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980301b.html>2,7K or -270,45°C while on earth we've reached about -273°C in artificial cooling experiments. So technically, we've had cooler places on earth although only relevant if you're an atom with a dislike for cold.
EDIT: After a bit of research I want to correct my cooling temperature statement. Turns out the best current example is Yale University, who have cooled a batch of one million fluoromethane molecules down to <url=http://physicsworld.com/cws/article/news/2012/nov/15/millikelvin-cooling-of-large-molecules-is-no-myth>30mK.

That's an abuse of Charles' Law. That law applies to ideal gases, and there's a whole host of assumptions that go with ideal gases that fall apart on a microscopic scale (for instance, the volume of the atoms will prevent the volume from reaching 0, because you can't put two atoms in the same place).

You're also incorrect about Heisenberg. A perfectly stationary particle, with no momentum, would in fact have an infinitely large uncertainty on its position. You couldn't measure its precise position without changing its momentum and making it non-zero. Heisenberg's uncertainty principle is not violated by absolute zero.

EDIT: A team at MIT in 2003 cooled a gas down to about 10[sup]-9[/sup]K.
http://web.mit.edu/newsoffice/2003/cooling.html

Well yes, I said mathematically zero volume, I realize that's not necessarily practical. And it asked for it, didn't you see how provocatively it dressed!?
I was actually going to mention the Third Law of Thermodynamics instead... then I got distracted and I don't know why I changed over to Uncertainty. Still, I maintain that there is some quantum mechanical reason why 0K is unreachable, I just don't remember what the reasoning was.

10-9K? Stupid physicsworld article from November writing like 30mK was some kind of new low! Still, even 30mK is far colder than the coldest known object in the universe, the Boomerang Nebula at 1K, although not as permanent.

I guess if you wanted to achieve 0K in a lab, then you constrain the position of the particles in your substance to the confines of the lab. This constraint would impose a uncertainty in momentum that would keep your substance imperceptibly above 0K, so I guess in a practical sense you're right. Still, in theory, Heisenberg doesn't stop a particle from having 0 momentum, so long as you don't mind that it could at that point be anywhere in the entire universe.

As for Charles' Law, I still disagree. The maths doesn't say that it has 0 volume at 0K because the maths doesn't apply in this case. You can't use an approximation in the cases where it doesn't apply.

EDIT: Y'know, I don't think I've answered anything in this thread, yet. Well, probably the most interesting thing I've seen on my physics course so far is just how much information can be gleaned from starlight. You can work out the mass of a star, its radius, its temperature, its brightness, whether it has planets orbiting, how big these planets might be, the composition of their atmosphere, the chemical makeup of the star, its distance, its speed, and sometimes its age, just by looking at it through a sufficiently powerful enough telescope and application of theory.

 

[DkLnBr]

Wow, everyone sounds so smart compared to me... The Heisenberg uncertainty principle, electron probability shell, quantum tunneling, quantum entanglement, feynman's formulation, etc... I'm just a talking chimp to you guys aren't I?
On Topic: Something that blew my mind back in high school was what my physics teacher told us. If you have a loaded gun that's perfectly parallel to the ground and were holding a bullet at the same height as the barrel. If you dropped the bullet and fired the gun simultaneously, both bullets will hit the ground at the same time.

How hard evolution is to some people? How hard is it? The Pichu get's happy and evolves to a Pikachu and give it a thunderstone and it evolves to Raichu, it's not that hard people!

But if Pichu evolves into Pikachu, then why are there still Pichus? Your move Athiests

 

[Pinkamena]

Non-contact heating-
How the hell is that ice cube heating up while not melting at all??

There is a piece of metal inside the ice cube, which is what's getting heated and glowing.