What would change if energy could be created/destroyed?

The thing is, this old style of physical thinking is obsolete. We now know the universe would lose a very basic element of symmetry in order for mass-energy to not be conserved.

From Wikipedia: “Noether’s (first) theorem states that any differentiable symmetry of the action of a physical system has a corresponding conservation law.”

It’s hard to overstate the impact of Emmy Noether’s work on physics. Modern physicists find it difficult to revert back to the manner of thinking their predecessors used before symmetry and group theory became so fundamental.

it can, if anti-matter comes in contact with matter, the matter would disappear. along with any energy contained therein.

@FluffyChicken bringing together a particle and it’s anti-matter opposite is the purest expression of matter-energy equivalence (E = mc^2) and conservation. Both particles are annihilated, but in the process produce a shower of new particles that carry off the total energy equivalent to their original combined mass.

I can’t think under that paradigm, sorry. What would we create energy from? What would we destroy it into? I suppose it would solve the energy crisis, since perpetual motion engines would actually work, but we would also probably be destroyed by large amounts of pure energy just appearing out of nothing.

@FluffyChicken The principle behind PET scanning is that matter-antimatter annihilation produces energy in the form of gamma rays, of a very predictable energy (511keV). If this energy just vanished, then this wouldn’t be possible.

there would be a big change than most of the laws would broke there would nothing like heat exists

Actually…energy is never ending… this is called Life.
And death cannot be….
This is the reality of those who have changes their way of thinking and acknowledges Truth as Truth….

Given the fact that E=MC^2, if energy could created and destroyed (besides changing it into matter), then matter could be created or destroyed as well. Both cause bad things to happen. Very bad things… Depending on what laws of physic our universe would end up having, there could be an inbalance between the likelyhood of the two events. In one universe, all space will become packed with matter, causing black holes everywhere. In another, everything is destroyed, leaving nothing… By conserving energy, our universe has prevented both of these things from happening.

If energy could be created and destroyed then the fundamental principles of chemistry and physics would be overturned.

@kess “Death cannot be”? Thousands of people die every day – death is a well established fact.

Keep in mind that free energy is being destroyed all the time in our universe. Order gets replaced by randomness.

The creation of new free energy is still a mystery. What would change? Perhaps new universes can be created.

@mattbrowne “Order gets replaced by randomness.” That’s entropy, not energy.

The picture of the vacuum coming out of quantum field theory is that virtual particles pop in and out of existence on short time scales. It’s as it they can loan mass-energy from the universe for a very short period of time but then they have to pay it back.

How this squares with Noether’s theorem? I don’t know.

Virtual particles do produce some effects on real matter (ex: g-2). There is only one instance I know of when virtual particles could be “promoted” to real ones and that’s close to the event horizon of a black hole (see: Hawking radiation). Note that even in this case, the net effect is not “free energy”. The energy radiated away is compensated by the loss of mass from the black hole.

@hiphiphopflipflapflop – I was talking about free energy. Free energy is being “destroyed” all the time in our universe and order gets replaced by randomness. Entropy increases.

@mattbrowne Gibbs free energy is not a conserved quantity, but total mass-energy is (averaging over “large” enough volume and time scales to avoid these transient quantum effects I mentioned previously) and I’m fairly certain that’s what the original question was asking about. The loss of Gibbs free energy in an isolated system is compensated by the gain in heat in terms of the system’s total mass-energy.