Wednesday Wonders: Let’s get dark (Part 2)

Last week in Part 1, I looked at failed scientific hypotheses, the scientific method, and how Einstein’s Special and General Theories of Relativity hold up and yet are completely incompatible with each other, mainly because one explains gravity very well but nothing on the quantum level, and the other is the opposite. Here’s the rest of the why of that. Cheers!

May the force(s) be with you

In physics, there are four fundamental forces. They are gravity, electromagnetism, the weak force, and the strong force. We’ve already met gravity, which works with enormous masses across great distances but doesn’t seem to really have much effect in the sub-atomic realm.

The electromagnetic force, mediated by electrons and photons, seems to work on both a macro and micro level. It gives us electricity, lightning, and a sense of touch — all rather large phenomena quite visible in the quotidian world. On a subatomic level, it gives us friction and holds solid objects together, among other things.

An ice cube, for example, is just the electromagnetic force acting on water below a certain temperature. The electromagnetic force is also why you don’t just fall through the floor.

The weak nuclear force facilitates one kind of subatomic particle changing into another via the exchange of Bosons. This force is essential for powering the fusion that keeps stars alive, as well as transforming one kind of particle into another.

Finally, there’s the strong nuclear force, which is responsible for keeping the fundamental particles that keep atoms together. It bonds the quarks to create protons and neutrons, then bonds those to create atomic nuclei, to which the electromagnetic force attracts elections, creating elements.

Now, here’s the funny thing. In theory, the strong nuclear force is much, much stronger than the force of gravity — if its force is set at 1, then gravity is 6×10-39. However, there’s a catch. Gravity’s effective range is infinite, while that of the strong nuclear force is only 10-15 meters.

This is the basic stalemate between Einstein’s Theories of Relativity and quantum physics. The former explains the gravitational force very well, but doesn’t do that with the others. The latter explains the other three, but really has dick-all that can explain the former.

It’s kind of like the ultimate Nerd-Fight Cage Match, really.

Is it elementary?

I find it kind of interesting that modern physics settled on four forces, though (and four dimensions, but I’m not bringing that into it) when the ancient world settled on four “elements.”

This was long before any kind of theory of atoms, but by the age of Alchemists, who sought the holy grail of turning lead into gold long before anyone even realized that the only way to do that was via nuclear fusion, the prevailing wisdom was this.

There were only four “elements.” They were earth, fire, air, and water. This four-split in human culture, at least of the Western European kind, became so prominent that it was ridiculous.

How many suits in a deck of cards? How many Gospels? How many cardinal directions on the compass?

And don’t forget those famous Elizabethan “humors” that you probably learned about in high school: Melancholic, Choleric, Sanguine, and Phlegmatic.

Finally, how many limbs do we have, not counting our heads?

Somehow, this tetrapartite symbolism crept into Western culture and while the initial concepts about which elements actually existed are laughably wrong, let’s take a look at those naïve assumptions one more time, and map them onto modern physics.

Alchemists’ elements: Earth, fire, air, water

Elizabethan humours: Melancholic, Choleric, Sanguine, and Phlegmatic

Physics forces: Gravity, electromagnetic force, weak force, strong force

In at least the first and the last cases, it’s a game of “one of these things is not like the others.” Earth — which you can think of as soil or dirt or the planet itself — is solid matter. The other three are plasma, gas, and liquid.

Likewise, gravity seems to be a force created by the existence of matter, but unlike the others has no apparent particle that transmits it.

Little trouble in big bang

The idea that the universe began with a so-called “big bang” started with Edwin Hubble, the person, when he proved that the universe was expanding in all directions.

It followed that if the universe was expanding now, it had to have started expanding at some point in the past, and rewinding the clock indicated that the entire universe had been a single point 13 or 14 billion years previously.

So much for the idea of the universe being created in six days in 4004 BCE.

But this led to all sorts of logical questions. What caused the Big Bang? What came before it? And how did everything we know in the universe come into being in that instant and after, since all the energy and matter we’d ever have to work with had to have been generated at that point?

The other big question: How will the universe end? Will the expansion continue forever, eventually slowing down and stopping as entropy reaches a maximum, leaving the place cold, dark, and empty? Or did that first bang only give a sufficient kick to reach a certain point before the whole thing started to contract again, eventually returning to that initial point, slamming everything together into a Big Crunch that would recreate the original singularity?

In 1998, Hubble the Telescope did its namesake proud by throwing a wrench into things.

A little push

It turned out that the expansion of the universe was not slowing down or reversing at all. No — it was accelerating, meaning that not only might it never reverse or stop, it might just keep on going forever.

But this brought up the biggest and still unanswered question: What was causing the acceleration?

If we continue with the explosion analogy for the creation of the universe — which isn’t really that accurate, since the Big Bang happened everywhere at once — there’s no way to account for the acceleration without adding some outside factor.

But imagine this scenario. You launch a firework into the air and it blows up like it’s supposed to, sending its colorful pyrotechnics and sparks outward in a short series of multi-colored showers that make the crowd ooh and aah.

Now, when you designed the firework, it was meant to be a five second air-burst at a safe height of 200 meters, expanding to a maximum diameter of maybe 110 meters if you launched a 20-centimeter shell.

After all, all of the mass and energy that would ever exist in that explosion was packed into that shell before launch; before the Big Bang.

But then, your shell gets up there, and not only does it hit its intended 110 meter burst size before five seconds, but it keeps on going and growing, gradually expanding faster than the initial 22 meter-per-second growth rate — and it never stops expanding.

This is kind of what the universe appears to be doing.

The universe has lost your luggage

Other discoveries indicated that galaxies were acting like they had a lot more mass than they should have, or that we were able to observe because of their rotation. This led to the postulation of the concept of dark matter.

Meanwhile, the accelerating expansion of the universe led to various hypotheses, including the idea of dark energy.

By the way, please keep in mind that the terms “dark matter” and “dark energy” really should not be taken literally. They’re placeholders to indicate two things. The “dark” part just says that we cannot detect them. The “matter” and “energy” parts just tell us that, at the moment, we’re looking for force carrier — i.e. particle/wave thingie — and a specific force.

It’s like the term “dark saber” in The Mandalorian. George Lucas just needed to pull something out of his ass to justify a light saber that was black — hence, technically, not involving light at all.

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The takeaway here, though, is that dark matter seems to be pulling on galaxies to affect their spin, while dark energy seems to be pushing on the universe to speed up its expansion.

The real scary part of this though, is that the fallout of these two ideas is that less than 5% of our universe is made up of the familiar matter and energy that we know.

None of the dark energy hypotheses has been tested yet, although I lean towards modified gravity, or MOND concepts myself, since these truly seek to reconcile the two theories of relativity and unite the fundamental forces at last.

Ether frolic II

My problem with the idea of dark energy and dark matter is that they could just be this generation’s ether and phlogiston. Maybe the acceleration of expansion is an error in the original measurements of the Cosmic Microwave Background.

Or maybe something about the inflationary period created an artefact that only makes it look like acceleration is expanding when it’s not.

There was a very long period after the Big Bang, called the Cosmic Dark Ages, before stars or galaxies even formed. This may have been when Dark Matter arose — or it may just be an era we can’t really peer through because fusion had not lit up the cosmos.

Finally, we cannot really discount universal inflation, which is when everything expanded much faster than the speed of light. This was possible because nothing was moving that fast. It was space itself that ballooned, so that anything that moved with it was moving at the same speed as space relatively — i.e., it was stationary, so no violations at all.

But, since space-time seems to be the macro-fabric that gravity acts on instantaneously but in an attractive and not repulsive manner, could inflation and not the dark ages actually have been the period when whatever dark energy might exist was created?

Could this also be how gravity got separated forever from the other forces? Who knows? However, since gravity also apparently has no particle that transmits its force, it also has no anti-particle, at least that we know of.

Finding a particle for it would probably lead directly to solving the dark energy problem, since gravity’s anti-particle would be the particle transmitting dark… well, at that point, it would probably just become anti-gravity.

One other mind-fuck in the basket. As noted previously, we have confirmed the existence of gravity waves, which ripple through space-time on a super-macro scale. But if gravity waves do exist, is there a way to observe them that will show their particle nature as well?

Because if we manage to pull off that trick, well then… Special and General Relativity are going to need to get a room.

Image Source, European Space Agency, licensed under (CC 4.0) International