Why can't you create or destroy energy?

Question

Sounds dumb..but i don't know the technicalities of it..

Answer 1

No particular reason--you just can't. Maybe in some other universe you could.



If you've studied mechanics a bit, you know that conservation of energy is equivalent to stating that the laws of physics are invariant under translation in time. Physics is the same now as it was a couple minutes ago and as it will be in a couple of minutes. This guarantees conservation of energy.



---Hey, good answer Epid. The only quibble I might make is that "temporally symmetric" might be read as encompassing both temporal translation and time flipping. Energy is conserved even if physics is assymmetric under a time flip, which actually appears to be the case. Just like momentum is conserved despite the fact that know that spatial parity symmetry is violated.



R--disregarding CP-violating interactions in particle physics, the laws of physics appear to be absolutely symmetric in time at the microscopic level, which guarantees conservation of ENERGY. Entropy and the second law of thermodynamics are something different--macroscopic phenomena that flow from the statistics of large numbers.

Answer 2

R@ is misleading. Energy is conserved, but useful energy called enthalpy will be converted to useless energy called entropy. Once it becomes entropic, the energy cannot be reconverted into enthalpic energy. That is, once Humpty Dumpty has fallen off the wall all the king's horses and all the king's men cannot put Humpty Dumpty back together again.



Our universe was injected with just so much energy Q = H + S; where H is enthalpic and S is entropic. In the beginning, a second or less after the big bang, S ~ 0 so Q ~ H, which means our universe was almost 100% pure useful energy. And isn't that amazing, why should our universe begin with useful energy like that? As you might imagine, with all that useful energy piled into a very tiny space, the universe was hotter than you know where...and then some.



But as H --> S, the temperature cooled down. Now the background temperature of our universe varies ever so slightly around 4 deg K....almost absolute zero. The universe is winding down; yet it still has the Q it started with. Only now the Q is mostly S, entropy.



Anyway, the bottom line is that we cannot create or destroy energy because Q remains fixed. So all we can do is convert it from one form to another and, ultimately, to entropic, useless energy.

Answer 3

Can Energy Be Destroyed

Answer 4

All the matter in the Universe had to have come from somewhere, and in that somewhere there has to be an origin. We use the word creation in order to describe that nothing is the source. The word implies a contradiction by which something becomes matter where in time it did not exist. A cell divides and becomes two. Where did the second one come from? It came from the relationship of the negative to the positive. It is electric and magnetic and the energy that bonds the two is antimatter; which is the helix. You can not understand this, it must be demonstrated and only then you may possibly grasp the concept that energy has always existed; therefore it need not be created and further more it can not be destroyed . In order to destroy something you would have to alter the state of matter. All matter has an electron, proton & nuetron of varying numbers . By splitting the atom there is a release of energy far greater than the inert state of existance, so you destroyed nothing.

Answer 5

Actually the Laws of Physics are temporally symmetric ONLY in theory

In practice it is impossible to create a perpetual motion machine



A perpetual motion machine is one which will for example take in energy at one point, do work (discharge energy at another place) and reuse the discharged energy to do work all over again.



It will go on and on endlessly and never need any more energy than what was initially required to set it in motion



This is impossible in practice



Hence energy can be destroyed. Well not exactly destroyed but degenerated to such a state that it is no longer capable of anything useful - this is called "entropy" and is a consequence of the second law of thermodynamics



The world is dying - global warming etc - because energy is dying - getting destroyed.



See



http://en.wikipedia.org/wiki/Entropy

Answer 6

Energy comes in many forms. What is apparent in SO many instances is what you see is what you get. Fire produces heat. Electricity provides electromagnetic force. Food heats the body, provides electrolytes in the blood and enables the brain to function. We can go on and on with the description of energy; but it all boils down to work. The expenditure of energy is overcoming a resistance. The potential may exist in the atom that has not been split so how can we destroy it? You can not. Creation is a word without merit. You can not create what already exists. For the benefit of logic the word should never have been made to describe something that we have not the answer.

Answer 7

I think you should work it out yourself in your mind.....



First think of a created/destroyed energy. Then if you try to figure it out you end up reaching at the sun.....Yes the solar energy is the prime source of energy.



For Eg let us take yourself. You do lots of things. So in this way, it might sound to you that you created the energy. But no. The food you eat is converted into the things you do. And from where do you get this energy in food ? If you ate meat, the animal that ate plants got the energy by doing so. So plants get the energy from the sun(the light and heat energy). And from where sun gets this energy ? By nuclear fusion. Hydeogen is converted to Helium in the sun. !!!!!!!!!



Hey!!!!!!!That's it!!!!!!!!!!From where does Hydrogen come from in the sun ??That might be an answer.

Answer 8

Because the laws of physics are temporally symmetric.



Not the answer you expected, but the right one. Emmy Noether showed that conservations laws are related to symmetries in the laws of physics - the famous Noether's Theorem.



In the case of energy, the related symmetry is that with respect to time.



Basically, what it means is that because the laws of physics do not change over time, energy is conserved.

Answer 9

lol, once you find out the answer you're looking for you should get into quantum physics, then you'll be asking how can you create or destroy energy ;)

Answer 10

well what i think is that energy cannot be created nor destroy.

if you said that you are going to destroy the sound dumb, i think you are going to hurts yourself. but you have to try,

Answer 11

It's a basic law of physics. Compare: Why does 2 + 2 = 4? It just does. Physics is based upon a number of immutable laws. Now, in special cases special things happen, but the laws of physics are generally true in 99.999% of life's situations.

Answer 12

Entropy is destruction. You can not destroy destruction.

Answer 13

Because it transfers into something else, like sound or light.

Answer 14

Hahaha, you're weird. I MADE MYSELF A SANDWICH.