My interest in physics probably peaked by sophomore year in college. Though it never completely waned.
Abstract
Black holes imply infinite gravity, a destruction of matter by all counts. But the laws of matter and particles don’t support this. Once a particle gets small enough, it starts acting in peculiar ways. Refuses to break down and starts disappearing. And reappearing in others (quantum entanglement).
2023 — where it started
My interest in physics probably peaked by sophomore year in college (though it never completely waned) and more recently I tend to offset reading classic literature with some occasional scientific or economic work which scratches the itch. As of late, this focus has been on black holes.
Black holes are formed from collapsed stars and have such intense gravity that they warp time and space. And as you may already know, black holes get their name because at a certain point — referred to as the “horizon” — nothing escapes, not even light.
However, I learned recently that not all light is sucked into a black hole — some of it escapes. Yet, given how intense gravity is nearby, photons of light will sometimes spin around multiple times before finally escaping and shooting off into space (at the speed of light). This is what gives black holes the “ring of fire” look:
If you look closely, you can see that the “rings” spin faster near the event horizon and slower the farther away they get. This is a visual representation of how black holes “warp” space-time.
Many of us already know how “tides” work with regards to bodies of water, but I’ll briefly reiterate since it preempts my primary discussion point.
Basically, in the image above, we can see that the Moon is exerting its gravitational field on the Earth’s oceans and it causes this sort of "squishing” that results in water levels to rise or fall depending on where you’re located on Earth and where the Moon (and Sun) are tangentially positioned. The “squishing” is a result of an unequal gravitational field, and in this case, it is a relatively small gravity (the Moon) being exerted upon a relatively large object (the Earth).
Now consider a black hole:
Black holes are former stars that collapsed in on themselves to form a “singularity”. This results in something very small that exerts an ENORMOUS gravitational field around it.
Now consider what would happen if an object — let’s say an astronaut — got sucked into a black hole:
The gravity exerted by the black hole on the astronaut would be drastically different between their head and toes, resulting in what Stephen Hawking coined as “spaghettification”. So yeah, Interstellar isn’t all that accurate in this regard :p
If any of you (like me) watched Interstellar and oft-crave the investigation of far flung galaxies than you are in luck. Today, we deep dive the most “practical” means of reaching nearby galaxies.
The nearest star (other than our Sun) thought to have a habitable planet is Tau Ceti which is 11.9 light-years from Earth
We’d have to travel at the speed of light for 11.9 years to reach it
The farthest humans have sent a spacecraft is the Voyager 1 which is now about 18 light hours from Earth
Anyone who was STEM major in college likely has some fundamental understanding of quantum physics. The basic idea is that on the quantum level — think atomic and subatomic — the classical rules of physics don’t apply. As in, the laws of motion (Newton), thermodynamics, and electrodynamics (Maxwell’s equations) don’t “work“ when we look at the behavior of subatomic particles.
Instead, they follow the behaviors defined by quantum mechanics. One of such odd behaviors is this phenomena known as quantum entanglement which essentially says that some particles cannot have their state described independently of the state of others.
In Einstein’s original thesis, he gives us an example where a man stands on a train platform and measures the speed of light and finds it to be equal to some value C. The man then hops aboard the next train and measures the speed of light once again and finds it to be exact same value. Now, the reason this should confuse you is because this is not how the classical laws of physics work. Consider the following illustration:
If the man boards the train and is headed towards the light source then you would expect the measured value of the speed of light to be C + (speed of train). Whereas if the man boards the train and is headed away from the source of light, then you’d have the same case as the illustration above and expect the speed of light to be C - (speed of train). What this implicates is that the speed of light is constant.
Now, the next step in explaining general relativity is a bit of a leap and can be hard to wrap your head around, but bear with me.
Our conception of “time” and “reality” are one and the same. That is, what we perceive each waking moment as the seconds tick by is our interpretation of “this reality”. And from our discussion above, we established that the speed of light is constant. Therefore — and this is where the big leap is gonna be, so try and wrap your head around this — our interpretation of time and reality is relative to the speed of light. You can think of it as “everything we see and do through every waking moment is relative to this constant thing: the speed of light”.
Finally, the last element to all of this, gravity.
The reason why gravity distorts time is because it warps the path upon which light must travel.
In the illustration above, we can see three objects with increasing gravitational fields. As light travels through space and approaches one of these objects, its path gets bent. What this means, is that light photons have to travel a longer path to cover the same “distance” (in our three dimensions that is).
So if you’re an astronaut standing near a black hole, light has to travel a longer path due to the immense gravitational field, but we have already established that the speed of light is a constant value C and that our notion of time is relative to it.
Gravitational collapse is known as “the contraction of an astronomical object due to the influence of its own gravity, which tends to draw matter inward toward the center of gravity” [1]. In other words, gravitational collapse occurs when an object in space grows too large and the force of its own gravity causes it to collapse in on itself.
What’s really interesting about this astronomical process, is that gravitational collapse is the fundamental mechanism for structure formation in the universe. Both the creation of stars and black holes follow this process (just in reverse order).
Consider the creation of a new star. Clouds of gas that exist throughout the universe will remain in equilibrium as long as the kinetic energy from the gas’s pressure remains in balance with the potential energy of its gravitational force [2]. However, when a cloud of gas grows too large and does not retain enough gas pressure to refute the internal force of its increasing gravity, it will collapse in on itself to form a new star (which is nothing more than a denser form of this collection of gas).
The photograph above was taken by the Hubble Space Telescope in 1920 and consists of dense clouds of interstellar gas which are in the process of creating new stars (which is why they are so aptly referred to as the Pillars of Creation).
Now consider the process in reverse. When a star reaches end of life, and has burned through its internal kinetic energy, it will follow a similar process (and collapse in on itself). However, the result is very different:
We can see outlined above that average sized stars collapse into “white dwarfs” and massive stars collapse to either “neutron stars” or black holes. Whether a massive star becomes a neutron star or black hole after gravitational collapse depends on its size. According to the Tolman–Oppenheimer–Volkoff limit, if a star is roughly double the mass of the Sun, no known form of cold matter can provide the force needed to oppose it’s gravitational contraction once started (which will continue unopposed until a black hole is formed) [3].
In short, gravitational collapse is responsible for the creation—and likewise demise—of our universe’s fundamental astronomy. And like most of things in nature, it comes down to a very simple relationship. In this case, gas pressure and gravity.
Like most galaxies, the Milky Way has a supermassive black hole at it’s center. The gravity of which keeps matter in orbit (such as stars and gas clouds). It’s no different than the Sun at the center of our solar system keeping the planets encircled. That said, the Milky Way is a relatively stable galaxy and the orbits of interstellar mass are fairly consistent. All of which goes to say that the black hole at the center of the Milky Way is pretty inactive:
But last week, the James Webb Space Telescope took some near-infrared images of a nearby galaxy referred to as Messier 106 (discovered by Charles Messier’s assistant, Pierre Méchain, in 1781) and the results are pretty astounding:
What you’ll notice is that Messier 106 is extremely “bright” and this is a direct result of the supermassive black hole at its center actively “swallowing up” matter. As gas, dust, (and even planets) get sucked into the downward spiral of the black hole, it results in the heating of matter and the emission of light.
The image reveals another striking feature of Messier 106: its extra pair of arms. Most spiral galaxies only have one pair of arms, but Messier 106 has an extra set, seen above as red wisps of gas which astronomers believe to be an indirect result of the violent churning around the black hole’s event horizon.
I dove into gravity and its implications in relation to time in a previous substack. And you’'ll remember that an increase in gravity leads to the slowing of time (or rather, our perception of this reality). But what I was thinking about more recently, is what happens if you take gravity and time to their logical conclusion?
For example, a black hole is gravity at its most extreme. Like in Interstellar, as you approach the event horizon time slows down to a crawl. And logically speaking, when you cross the event horizon gravity can be considered infinite (given not even light escapes and therein our conception of this reality):
— I love ChatGPT bro —
But here’s what I wanna focus on, what happens when you take a black hole to its negative infinity? First of all, what’s the opposite of a black hole? Does such a place as (true) 0G even exist? Imagine something in space that doesn’t bend light (and thereby slows time) but instead contracts it. A reduction of all gravitational force such that the result is an entity traveling at (or damn near) the speed of light.
Black holes and their singularity defy nature. And yet, we’ve confirmed they exist. Given the sheer scale of the universe and the inherent possibilities that come with that scale, is it really that absurd to consider something that reduces gravity to 0? That enables traveling at the speed of light?
I came across this picture on Instagram. The first simulated image of a black hole, calculated in 1978:
And my first thought was “why is one side brighter than the other?” Key-in ChatGPT:
Relativistic beaming. This is the key reason for the asymmetry. If the black hole is surrounded by a rotating accretion disk (a disk of superheated gas and matter spiraling in), then parts of the disk are moving toward us and parts are moving away. The side moving toward us has its light blue-shifted and boosted in intensity due to special relativity. The side moving away has its light red-shifted and dimmed.
As light spins around the event horizon of the black hole, it either gets sped up (blue shifted) or slowed down (red shifted), which gives the appearance of one side being “brighter” than the other.
Black holes imply infinite gravity, a destruction of matter by all counts. But the laws of matter and particles don’t support this. Once a particle gets small enough, it starts acting in peculiar ways. Refuses to break down and starts disappearing. And reappearing in others (quantum entanglement).
Gravity on the infinite scale applied to matter pushes particles into different space times. Will occasionally run across our fabric and we’ll see a particle blip.
If you fall into a black hole, there are infinite parallel universes you could be projected into. While you could die, there is a higher likelihood that your particles will be compressed in to a random enough stream where you retain self in a different weave of the spacetime.
