What’s the bloody matter now?

There’s too many to choose from! There’s basic normal matter, made up for tiny, constantly vibrating particles. [That’s what they say, for now. Get ready for the revamp when they prove string theory!!] Matter is anything that has mass and occupies space. But mass is defined as the amount of matter in something. Hmmm. Matter can exist in 5 states/phases: solid, liquid, gas, plasma, and Bose-Einstein Condensate [BEC]. Plasma is highly ionised electrically-conducting gas. BEC is the humungous multi-nucleic ball formed when a group of atoms are frozen at teperature VERY VERY close to Absolute Zero. At this state, there’s no way to tell atoms apart.

Calling these particles simple atoms and molecules would be gross evidence that one is still reading Amish textbooks [sorry, no offence], we shall pay tribute to string theory for a bit and relate to these particles as being made up of quarks [of which there are six types/”flavours”: up, down, strange, charm, top and bottom], which are in turn made of “tiny vibrating strands of energy” that we call strings.

According to string theory [currently there’re 5 versions of it], there’re either 10 or 11 dimensions [at least], and depending on how the strings are vibrating into these dimensions [whether it’s clockwise or anticlockwise wrt to a particular dimension is also important], determines whether the string is observed as matter [fermions] or forces [bosons]. As one can realise, this is an upgrade from Einstein’s equation that related matter and ebergy. Now it’s incorporating forces which are manifestations of energy transfer.

So the complete list of bosons and fermions observed or hypothesized so far can be found here. The details of how they come up with the theories is quite…scary. I mean, it looks like they’re inventing Greek all over again, and it might as well be the case.

But by now, we notice the popping up of the word “anti” almost everywhere. Anti-matter is, analogously speaking, the hole left behind in dough when a ginger-bread man is cut out from it using a man-shaped cutter. So in this analogy, the dough would be energy, the force of exertion on the dough by the cutter would be extreme conditions like abnormally high temperature or pressure [or both], the cutter itself would be the strict laws of physics that don’t allow just about any “shape”/imaginary particle that you can think of to come into existence, and the unbaked ginger-bread man would be the particle. Scientifically, anti-matter is a fundamental particle with its electrical charge reversed. To make it easier, if the ginger bread man is inserted back into the “hole” [somehow], and “glued back” [somehow], we can assume the energy released would be equal to the energy exerted by the cutter in the first place. So that’s essentially what anti-matter is. An evil twin. If matter and antimatter meet, they release energy. *And neither can exist independently*. Every type of particle has a dedicated anti-particle.

**This raises a very important question and with good reason. If matter and anti-matter cannot exist independently, why does the universe exist? The matter that makes up the universe should have had more than enough time to collide with anti-matter and become energy in 15b years right? Well, you might be partly right. The theory now is there was already asymmetry between matter and antimatter in the Ball before the Big Bang. When the Bang occurred, antimatter combined with matter and released energy in the form of energy. The surplus matter eventually formed up galaxies and constellations. The energy released is STILL observable as Cosmic Background radiation. It became radiation because of the Doppler shift “stretching” [in terms of wavelength] the photons into microwaves.

But anti-matter isn’t just the stuff of science-fiction or astronomy/theoretical physics journals. We apply it nowadays when we get PET [Positron Emission Tomography] scans done.

Phew. Then there’s strange matter. While normal matter is composed of only the up and down quark and electrons, strange matter is composed of up, down and strange quarks. Strange matter is ultra-dense and is theorized to exist within ertain massive neutron stars, whose intense mass has crushed its constituent atoms into quarks [only] during their collapse. These strange quarks are bound to each other directly; hence the name starnge matter. Some believe that strange matter, despite the enormous pressure that forms it, is stable outside such pressures once formed.

On a side note check out Chemical Galaxy.

Dark matter was discovered when scientists used different methods to estimate the mass of galaxies by the amount of brightness. One answer was about 400 times bigger than the other. Given that the two methods were equally valid, scientists theorize that the upto 90+% of the universe is made up of missing matter, or matter that cannot be seen. The two calculations were done this way or that way. The former employs an application of the Doppler effect, while the latter involves estimating how many stars there are based on the amount of light reaching the earth from a particular galaxy. No one knows what dark matter should be like. Some think it’s made of ordinary matter whith special chracteristics in special circumstances, while others think it’s not made of ordinary matter at all.

Why might dark matter research might be intersting to pursue? It determines the future of our universe! Any universe modeled from the Big Bang theory can have three possible paths of evolution. If the universe is closed, the “bang” makes it expand for a bit, but gravity catches up soon enough and so, in this scenario, there’s a recursive theme of endless Big Bangs and Big “Crunches”. If the universe is open, the “bang” is enough to overcome effects of gravity and the universe expands forever. A “flat” universe will stop expanding cos the gravity is just enough to stop the acceleration due to the “bang”, and stay that way after a while…[a LONG while]. The variant in all three is the amount of dark matter! Dark matter will contribute to the total mass. The more dark matter, the more massive our universe.

And finally there’s exotic matter, which is connected to dark matter in some way. It is good to think of exotic matter as the mutated version of matter, rather than an opposite. Exotic matter has a negative energy density and a negative pressure or tension that exceeds the energy density. There’s another form, a theoretical particle called a “tachyon”, that has [mathematically] imaginary mass, which subsequently demands the tachyon to always move at speeds greater than c.

All known forms of matter have positive energy density and pressures or tensions that are always less than the energy density in magnitude. In essence, while matter exerts gravitational pull due to mass, exotic matter exerts a push [anti-gravity, in a sense]. Using this “theory” scientists and sci-fi writers come up with ideas of stable wormholes [a blackhole as an entrance and a “white hole” [made of exotic matter] as the exit] and Alcubierre warp drive.

All this talk of gravitational repulsion brings us to the matter of antimatter. Which way does antimatter fall, in a vacuum? Of course, to determine that experimentally is VERY hard, cos antimatter is already so hard to isolate and in such small quantities [usually at individual particle level], gravitational interactions take a backseat to the EM, weak and strong nuclear interactions. So. IF antimatter’s found to have anti-gravitational properties, it might explain why antimatter is so rare in the vicinity of matter..on a cosmological scale.

Which matter are we talking about again?


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