The Quantum Universe
Exploring the structure of empty space.
By James Dwight Hartsell, July 11, 2017. 5/30/18: added June 2018 S.A. article18
If you are seeing this as a printed copy, the latest version is at www.jdhartsell.com/quantum.
Recent discoveries have made it possible for me to understand the universe well enough for my purposes. It is nothing I could have imagined.
When you toss a rock into a still pond, ripples (waves) flow out in a circular pattern from where the rock hit the water. Water is the medium through which the waves travel. For sound waves, the medium is air, like ripples travel on water, but sound waves are spherical in all directions. Einstein predicted, and it has recently been proven, that gravitational waves flow out from, for example, merging black holes. So what is the medium that gravitational waves travel through? It can't be empty space. The height of a gravitational wave is 1% the size of an atom! Wave length is about 47 times the diameter of Earth, about 750,000 miles! But scientists have finally been able to detect these waves, 100 years after Einstein mathematically predicted them (see LIGO, Laser Interferometer Gravitational-Wave Observatory).
The speed of light is 186,282 miles per second, not infinite as you would expect in empty space. If it was infinite, Einstein's E = mc2 says that energy would be infinite. Solving the equation for mass, m = E/c2, says that mass would be zero. The universe would not exist. So there is something that slows down the speed of light.
Gravitational waves and the speed of light mean we need a medium that gravitational waves travel through, and something that light has to plow through to limit its speed. As it turns out, the speed of light in empty space is indeed infinite, but space is not empty. It is filled with quantum foam, quadrillions of times smaller than the nucleus of an atom, that holds back the speed of light, and provides a medium for gravitational waves. It forms the fabric of the universe. Quantum foam is also called spacetime foam.
From A Review of the Universe1: "By combining the laws of quantum mechanics and general relativity, it is deduced that in a region the size of the Planck length (10-33 m), the vacuum fluctuations are so huge that space as we know it "boils" and becomes a froth of quantum foam."
A reminder about atoms: If an atom was as big as a football stadium, the nucleus would be the size of a pea. The electrons in orbit would be whizzing around in the stands. The nucleus is made of protons and neutrons, different numbers of them for different atoms. Protons and neutrons are made of quarks. So, an atom is made entirely of electrons and quarks. There are three quarks in a proton or neutron.
Spacetime foam is like an energy field. Virtual particles and anti-particles, like quarks, constantly appear and immediately disappear out of this energy field. It is a roiling, seething sea of activity. At any one instant empty space is filled with short-lived quarks, electrons, and other particles.
Entanglement is the essential ingredient that knits spacetime together into a smooth whole.4
From Science News14: Theoretical physicist Mark Van Raamsdonk calculated that space without entanglement couldn't hold itself together.
Paraphrased from the book Beyond Biocentrism2: If you shine a purple laser at certain crystals, purple photons (packets of light) are converted to two red photons, each with half the energy (frequency) of a purple photon's energy (frequency). It is like saying the purple photon was split into twin red photons. These two red photons fly off in different directions. If you do anything to one of the red photons, the other will react, no matter how far apart they are, even across the universe. If you polarize one photon vertically, the other will instantly polarize horizontally. Like two sides of the same coin. It happens simultaneously. It has been proven in the laboratory over a distance of seven miles.
As virtual particle pairs materialize in the vacuum of space, an electric field has been used to keep them from disappearing back into the vacuum. These particles will be entangled. Whatever you do to one will instantly affect the other.
Quantum entanglement has been a great mystery ever since Einstein's time. But very recently, theoretical physicist Juan Maldacena3 has figured it out. Entangled particles are connected by an Einstein "wormhole", or gravitational tunnel. Inside the wormhole time and space are zero. It explains it all. Beautiful.
Here's how I picture wormholes between engangled particles. Imagine an extremely thin & flexible short piece of tubing. Put two marbles inside so that they are touching. Say that the marbles are two halves of the same particle. Grasp each marble and pull them apart as far as you can. The inside of the stretched tubing is a wormhole, and inside the wormhole, space and time are zero. A signal from one marble to the other will arrive instantly, faster than the speed of light, no matter how far apart they are.
So now take a breath. Quantum foam and entanglement are connected. Each pair of particles and anti-particles materializing out of quantum foam are entangled for their very brief life, and connected by a wormhole. Empty space is filled with a foam of short-lived wormhole-connected virtual particle pairs.
From Scientific American3: "Quantum mechanics' entanglement and general relativity's wormholes may be equivalent."
Here is what theoretical physicists are finding in their latest math. Einstein's general relativity wormholes are equivalent to entanglement in quantum mechanics. This means entangled particles "connect" by wormholes. These wormholes are like threads and there are lots of them. THEY WEAVE TOGETHER TO FORM THE FABRIC OF SPACETIME.
Spacetime Foam = Dark Energy?
I had a thought that perhaps Dark Energy and spacetime (quantum) foam are the same thing. Dark Energy, or vacuum energy (Einstein's Cosmological Constant), is what makes the universe expand. Quantum foam is the fabric of spacetime. As the universe expands, both Dark Energy and spacetime foam fill the entire universe and maintain the same "strength". It looks like my thought is correct.
The problem has been that there is far too much energy in spacetime foam to consider it the same as Dark Energy.
But, a new study5 postulates that the universe is expanding due to fluctuations in spacetime foam. The fabric of spacetime is subject to wild fluctuations, oscillating at every point between expansion and contraction. But the study claims that the effects of vacuum energy are actually self-cancelling, which brings down the energy density to a reasonable value. Their explanation says that this is consistent with Dark Energy being the same as spacetime foam.
An article6 by John P. Millis, PH.D, dated March 2, 2017 asks if Dark Energy is a property of Space-Time. "There is a possibility that Dark Energy is the result of virtual particles being created, then annihilating, in the quantum foam of the universe. It seems like a perfect candidate for Dark Energy".
Many physicists now believe that spacetime is the result of entanglement, not the other way around. You can think of spacetime as being built (emergent) from entanglement.4
Time is an emergent phenomenon that is a side effect of quantum entanglement. The same goes for emergent space.
According to Reginald T. Cahill17, space and matter are emergent phenomena.
From Scientific American7 "Once the dynamics of entanglement are clearer, scientists hope to comprehend how spacetime emerges, just as the microscopic movements of molecules in the air give rise to the complex patterns of thermodynamics and weather". Key phrase is "how spacetime emerges". In the same article there is "Perhaps what we think of as gravity and spacetime is just another way of looking at the end product of entanglement."
From Quanta Magazine16 "Normally physicists think of entanglement as spanning space, but a growing body of research is investigating how entanglement can span time as well."
For emergent gravity, see Quantum Gravity below.
Matter and Mass
Quarks that make up protons have a "base mass" that comes from the Higgs Field, but it is only 2% of their actual mass.
From Astronomy magazine, Nov. 2012: "Extra mass in a three-quark configuration (like the proton) comes from the virtual quark antiquark pairs that pop up and disappear in the region around the three constituent quarks. Most of the actual proton mass does not come from the three masses of the quarks but from interactions and kinetic energy of these virtual pairs."
From Scientific American8: The rest mass of quarks accounts for only 2% of the mass of the proton. The other 98% arises largely from the actions of gluons (a force carrier that keep protons and neutrons intact). Quarks and gluons almost never live in isolation. They survive as free particles for less than 3 x 10-24 second. Gluons bind themselves and quarks together into longer lived particles.
Sept. 14, 2017: It seems reasonable to me that an atom's orbiting electrons can be (and maybe constantly) replaced by virtual electrons popping out of quantum foam. This could happen when an electron is close enough to a virtual electron-positron pair that it disappears with the virtual positron while the virtual electron takes it's place. This would mean there are no permanent electrons. By the same token, the quarks that make up protons and neutrons of an atom's nucleus could constantly be replaced by virtual quarks while the primary quark disappears with a virtual antiquark. This would mean atoms are in a constant state of flux.
A long time ago I read that philosopher Bertrand Russell said that a particle can be defined as "being it's history". So true.
One of the most important articles I've read is Scientific American's "The Glue That Binds Us", about the workings of protons8. The article mentions quantum foam inside the proton, and a sea of short-lived quarks, antiquarks, and gluons popping in and out of existence. I emailed one of the authors and asked if the primary quarks in a proton/neutron are also short-lived and constantly replaced by virtual quarks from the quantum foam. He said "you ask a very good question". He wrote 4 paragraphs, CC'd the science writer for the lab where he works (Brookhaven National Laboratory), and said a second time "good question". He basically said "yes, if the virtual quarks have enough momentum". This was before my idea of primary quarks disappearing with a virtual antiquark, leaving the virtual quark to take the primary quark's position.
Sort of going along with this, and also my credibility, a few years ago I had an online Astronomy magazine forum topic "Preservation of relativistic mass in the singularity of a black hole". If mass of a proton is from relativistic motion of it's constituent quarks, how do you explain mass of a singularity when it has zero dimension? A theoretical cosmologist joined the discussion and said to me "I like the way you think".
We know HOW gravity works from Einstein's relativity. But WHY does it work?
Emergent gravity springs from the quantum entanglement of small bits of spacetime information.12
Physicists have become excited about the idea that gravity is an emergent phenomenon.13
From Science News14: "Entanglement could be the secret ingredient that unifies incompatible views into a theory of quantum gravity."
From MIT News15: "The laws of gravity holding together the universe may not be fundamental, but arise from something else; quantum entanglement. Also: Gravity may emerge from entanglement. The geometry, or bending, of the universe as described by classical gravity may be a consequence of entanglement, such as between pairs of particles strung together by tunneling wormholes."
Quantum mechanics is not just an add-on to gravity - it is the essence of the construction of spacetime.3
The June 2018 Scientific American has a good article "What is Spacetime?" by George Musser18. Some takeaways: There are many ideas for a quantum theory of gravity, but competing approaches all say space is derived from something deeper. Quantum entanglement seems to be more primitive (at a lower level) than space. Entanglement provides a link between the presence of matter and the geometry of spacetime. More entanglemnt implies weaker gravity, that is, stiffer spacetime. Entanglement is what knits bulk space into a continuous whole. Correlations in the electromagnetic and other fields are a residue of the entanglement that binds space together. The ubiquity of entanglement explains the universality of gravity. The degree of entanglement defines a notion of spatial distance.
The Speed Of Light
It is well established in relativity that energy and mass are interchangeable. But, you cannot say E = m because they are not in the same units of measure. There needs to be a conversion factor. This factor needs to be distance2/time2, which is a speed constant squared, for example (meters/second)2. Through various theoretical approaches this constant worked out to be 186,282 miles per second, which is the speed of light!
Solving Einstein's formula for the speed of light, you get c = √ E / m . If you measure energy and mass, you can calculate the speed of light. So there is something about the speed of light that makes it a conversion factor between energy and mass. From PhysicsForums9: "If you want to obtain an energy from a mass you have to multiply it by a velocity squared, and the ONLY universal constant in general relativity with the right dimensions is just c". But it doesn't have to be the speed of light - it can be the speed of any massless particle, like the speed of gluons.
What if the speed of light was faster? From Worldbuilding Stack Exchange11: "By carefully adjusting the constants, you could make it so that most things stay more or less the same. However, there will be inevitable changes in the details, especially forget about Earth's magnetic field (and associated effects, like polar lights), permanent magnets, magnetic hard disks, golden gold and liquid mercury. Also a lot of electric technology (especially motors and generators, as well as coils for circuits) depend on magnetic fields. This would negatively affect all electric technology."
So, again, things are as they are because the speed of massless particles is what it is.