In the last few weeks, I have spent some time thinking about universe and how it was created. One of the common following question on this subject came to my mind: “How was the universe created if physics states matter can neither be created nor destroyed?”. I spent hours and hours researching this topic and decided to put all the research in one article.
At the end of the article I will also write about what happens with energy from our bodies after we die.
The First Law of Thermodynamics
The law of thermodynamics, also known as Law of Conservation states, that energy can neither be created nor destroyed; energy can only be transferred or changed from one form to another.
The Law does not specify that it is the same principle with matter. However, Albert Einstein wanted to explain that mass and energy are essentially equivalent with the famous E = mc^2.
Because Einstein clarified that mass is type of energy, we can say that 1st law of thermodynamics also applies to mass.
Conservation of energy can be rigorously proven by Noether’s theorem as a consequence of continuous time translation symmetry; that is, from the fact that the laws of physics do not change over time.
If we are about to use The First Law of Thermodynamics, we must clarify what a close system is. We can think about it this way: We drew an imaginary circle. If the imaginary circle is closed, energy (potential and/or kinetic) must stay the same. If it changes, the system must be either not closed or we have neglected amount of energy coming or leaving the circle.
Expansion of the Universe
Universe is expanding faster and faster (because of Dark Energy), so how can the energy inside of it stay the same?
There are stars, planets, galaxies, globular clusters – everywhere, matter and energy seem to exist, and is constantly rushing off in all directions. Because the universe expands the distance between stars and galaxies increases. It means that gravitational energy decreases.
As space expands, it releases stored up gravitational potential energy, which converts into the intrinsic energy that fills the newly created volume. So even the expansion of the universe is controlled by the law of energy conservation.
According to physics, all the matter and energy in the universe now, existed in some form at the Big Bang.
What is the total value of energy then?
That question does not have a proper answer. Thermodynamics does not state what value the total energy should have. However, most physicists now believe O.
It could be anything, but whatever value it is now, it was at the very beginning of the universe.
Can energy be spontaneously be created and destroyed?
Quantum mechanics states that, on a very, very tiny scale and for very, very, very short lengths of time, energy can be spontaneously be created and destroyed. It spontaneously appears from the void of spacetime, exist for a tremendously short amount of time and then disappear again.
What was Stephen Hawking’s opinion on this subject?
Stephen Hawking tried to answer that question in his book “A Brief History of Time”. His answer is based on the uncertainty principle:
If we take that the total variance of energy of the universe to be ΔE=0ΔE=0, then, according to this principle, you can have Δt→∞Δt→∞ and then, the universe can exist for an indefinite amount of time. The stated fact is that the total amount of energy of the universe is exactly 00. The reason is that matter has “positive” energy from it’s mass (E=mc2E=mc2) which is exactly balanced by “negative” binding energy (electrons in an atom, atoms in molecules, planet orbiting stars, stars clusters, galaxies, galaxies clusters, superclusters, etc.). Thus, the universe would have a total amount of energy equals to 00.
To answer the question about the “creation of energy”: it is sufficient to say that in the quantum mechanics realm, it is perfectly allowed to “borrow” energy from nothing, as long as the time when the energy is borrowed does not violate the uncertainty principle. This is a real effect that leads to spontaneous creation of particle-antiparticle pairs which have (or may have) a measurable effect (lamb shift, Hawking radiation, Casimir effect, spontaneous emissions, etc.). These particles are also called “virtual particles” as they do not exist freely and cannot be measured directly. Thus, according to Hawking, the Universe could have spawned from such a quantum fluctuation if the total energy borrowed is 00.
Where does our energy go when we die?
Roughly 20 watts of energy course through our body. However, unlike universe, humans are not closed (get energy through food and get it out by expelling waste). After we die, our energy does not die with us. Collection of our atoms is repurposed, so they always stay in universe and they will always be there (they will continue to echo through space until the end of time).
Our Universe exists as matter vs vacuum. Matter replacing vacuum gains velocity, which causes matter to gain angular momentum, which generates mass, which generates gravity, all of which is expressed as energy. How physics works is easy and demonstrable in every way. How or why the physics of our Universe began is a total and complete mystery.
All laws of physics that we know of are the result of observation, formation of hypotheses, making predictions, and testing them. Conservation of energy is one such law. If energy could be created or destroyed, all our ideas of how the world works would have to be modified in some way (and we’d learn something very perplexing). But so far, energy seems not to be created or destroyed.
However, the statement that energy cannot be created or destroyed does not have to apply to the universe’s creation, it could only apply in the universe after it was created.
All in all, we do not know yet exactly what happened the moment universe began. We are still working on the physics of it.
Writen by: Sara Nadzak