Claim: Energy cannot be created or destroyed; it can only change forms or be transferred from one form to another. Energy (and therefore potential matter) appears to have always existed.
Reply: Energy cannot be created or destroyed; it can only change forms or be transferred from one form to another" reflects the law of conservation of energy and is correct. The inference, however, that energy (and therefore potential matter) appears to have always existed is not. The second law of thermodynamics states that the total entropy (a measure of disorder) of an isolated system always increases over time. This law introduces the concept of the arrow of time and the idea that natural processes tend to lead to increasing disorder and less usable energy. In other words, while energy can be transformed and transferred, not all transformations are reversible, and the total amount of usable energy in the universe tends to decrease over time, leading to the heat death of the universe. According to the prevailing scientific understanding, the universe began as a singularity in an extremely hot and dense state, and both energy and matter emerged from this initial state. This concept challenges the idea that energy and matter have always existed in the same form. In modern physics, there's a concept of the quantum vacuum, which is not empty space but rather a seething sea of virtual particles and energy fluctuations. These phenomena are subject to the principles of quantum mechanics and may give rise to the appearance of particles and energy from "empty" space. However, these virtual particles are not the same as "potential matter" in the traditional sense. The existence of eternal energy or matter, these concepts remains speculative and has not been demonstrated through empirical evidence or established scientific theories.
The existence of an arrow of time implies that the universe has a finite past—there was a point in time when the universe had lower entropy and was in a more ordered state. Quantum fluctuations and phenomena associated with the quantum vacuum are subject to the principles of quantum mechanics, including causality. Quantum fluctuations involve random changes in energy levels within a quantum system. These fluctuations are considered inherent to the nature of quantum fields, but they do not necessarily violate causality or require a continuous extension into the past. The question of whether quantum fluctuations extend back eternally in time relates to broader cosmological considerations. According to current scientific understanding, the universe itself had a beginning in an event commonly referred to as the Big Bang. This event marked the initiation of spacetime, matter, and energy as we know it. Therefore, the origins of quantum fluctuations and the quantum vacuum would be tied to the initiation of the universe itself. Quantum fluctuations might have played a role in the early universe, including the period of cosmic inflation shortly after the Big Bang. During cosmic inflation, rapid expansion occurred, and tiny quantum fluctuations in the energy density of spacetime are thought to have been stretched to cosmic scales, seeding the structure of galaxies and cosmic microwave background radiation that we observe today. The connection between the arrow of time, the origin of the universe, and the nature of quantum phenomena raises philosophical questions about causality, the nature of time, and the fundamental laws of physics. The finite past implied by the arrow of time and the observed expansion of the universe suggest that phenomena like quantum fluctuations and the quantum vacuum did not extend back eternally in time. Rather, their origins are intertwined with the initiation of the universe itself, as described by cosmological theories like the Big Bang theory.
The prevailing scientific model, known as the Big Bang theory, suggests that the universe began with a singularity, a point of infinite density and temperature, around 13.8 billion years ago. The laws of physics describe the behavior of the universe, and they are thought to have existed since the beginning of the universe. The physical world and the laws that govern it are interdependent. The laws of physics describe how the physical world behaves, and the behavior of the physical world is governed by these laws. In other words, the laws of physics are the fundamental rules that determine how the physical universe operates.
There is motion. Things move when potential motion becomes actual motion. Only when potential motion exists ( the possibility to instantiate actual motion ), actual motion can be instantiated. Each thing beginning to move is moved by a cause. The sequence of motion cannot extend infinitely. Therefore, there must be a first mover, that puts motion in motion which is God.
According to most astrophysicists, all the matter found in the universe today was created at the very first moment of time, thought to be about 13 billion years ago. The universe began, scientists believe, with every speck of its energy jammed into a very tiny point. This extremely dense point exploded with unimaginable force, creating matter and propelling it outward to make the billions of galaxies of our vast universe. Astrophysicists dubbed this titanic explosion the Big Bang.
S W Hawking The large scale structure of space-time 1973
Whether this could happen, and whether physically realistic solutions with inhomogeneities would contain singularities, is a central question of cosmology and constitutes the principal problem dealt with in this book; it will tum out that there is good evidence to believe that the physical universe doesin fact become singular in the past. It would imply that the universe (or at least that part ofwhich we can have any physical knowledge) had a beginning a finite time I!'go. However this result has here been deduced from the assumptions of exact spatial homogeneity and spherical symmetry.
Mithani, Vilenkin Did the universe have a beginning? 20 Apr 2012
There are three popular scenarios: eternal inflation, a cyclic universe, and an “emergent” universe that exists for eternity as a static seed before expanding. Here we shall argue that none of these scenarios can actually be past-eternal. Did the universe have a beginning? At this point, it seems that the answer to this question is probably yes.2 Here we have addressed three scenarios which seemed to offer a way to avoid a beginning, and have found that none of them can actually be eternal in the past. Both eternal inflation and cyclic universe scenarios have Hav > 0, which means that they must be past-geodesically incomplete. We have also examined a simple emergent universe model, and concluded that it cannot escape quantum collapse. Even considering more general emergent universe models, there do not seem to be any matter sources that admit solutions that are immune to collapse.
P. James E. Peebles The Evolution of the Universe October 1, 1994
Some 15 billion years ago the universe emerged from a hot, dense sea of matter and energy. As the cosmos expanded and cooled, it spawned galaxies, stars, planets and life
The Big Bang created all the matter and energy in the Universe. Most of the hydrogen and helium in the Universe were created in the moments after the Big Bang. Heavier elements came later.
Xinyong Fu THE ORIGIN OF ENERGY FOR THE BIG BANG 20 Nov 2003
The idea that the present universe----billions of galaxies----was produced in a big bang about 13 billion years ago is approved of by most of today’s astrophysicists.
The Origins of the Universe MARCH 1, 2016
Everything we know in the universe – planets, people, stars, galaxies, gravity, matter and antimatter, energy, and dark energy – all date from the cataclysmic Big Bang. While it was over in fractions of a second, a region of space the size of a single proton vastly expanded to form the beginnings of our universe.
The Birth of the Universe
How and when did the universe begin? Approximately 13.7 billion years ago, all the matter and energy in the universe were created in an enormous explosion known as the “Big Bang”.
How did the universe start?
Most physicists believe the universe was born in a big bang 13.8 billion years ago. In it, the energy making up everything in the cosmos we see today was squeezed inside an inconceivably small space – far tinier than a grain of sand, or even an atom. Then, this unimaginably hot and dense cauldron – for whatever reason – ballooned at a terrifying rate.
Lars Bergström Cosmology and particle astrophysics 2006
The Standard Model of cosmology is the Hot Big Bang model, which states that the Universe is not infinitely old but rather came into existence some 13 to 14 billion years ago. Also, the fact that the oldest objects found in the Universe – globular clusters of stars and some radioactive isotopes – do not seem to exceed an age around 13 billion years gives strong evidence for a Universe with a finite age, as predicted by the Big Bang model.
Clara Moskowitz Fact or Fiction?: Energy Can Neither Be Created Nor Destroyed August 5, 2014
The law of conservation of energy, also known as the first law of thermodynamics, states that the energy of a closed system must remain constant—it can neither increase nor decrease without interference from outside. The universe itself is a closed system, so the total amount of energy in existence has always been the same. The forms that energy takes, however, are constantly changing.
Cosmos Big Bang
The ‘Big Bang’ is the model for the formation of our Universe in which spacetime, and the matter within it, were created from a cosmic singularity. The model suggests that in the 13.7 billion years since the Universe began, it has expanded from an extremely small but incredibly dense and hot primordial fireball, to the enormous but cold and diffuse Universe we see around us today.
Last edited by Otangelo on Sat Aug 19, 2023 8:45 am; edited 1 time in total