Theory of Gravity

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ref: How the Universe Works: Theory of Gravity

  • Gravity of earth allows us to travel from any point of earth to any other point in exactly 42 min, provided we go thru the earth in straight line
  • Escape velocity is 250K miles/hr
  • Gravity is due to curvature of space time fabric
  • Gravity gives objects Kinetic and Potential energy
  • ZeroG is an illusion..we know that all objects fall to earth at the same rate irrespective of mass….so in zeroG ride, the plane and person are free falling at the same rate and so maintain the same position relative to each other and so feel the illusion of weightlessness…
  • Acceleration is the same as Gravity
  • Upto 300k yrs after the big bang, the universe was so dense that light couldn’t excape, so to listen to big bang, we need to hear it’s gravity waves…
  • Scientists have designed an experiment to identify this by using lasers, but are yet to read the gravity wave signal
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Galaxy or Black Hole: What comes first?

ref: How the Universe Works S03E07 – Did A Black Hole Build The Milky Way

We know that there is a Black Hole at the center of every Galaxy, so the Question is What comes first?

The first generation of stars in the Universe after the big bang are super massive and so burn out quickly and their core became a black hole.

These black holes start small but over time eat matter and grow massive…and now sit at the center of galaxies….

This is a simple beautiful theory, but there’s a problem….We see Quasars in the very early universe…

Quasars light up the entire universe…the outshine 100s of galaxies put together…how can they emit that much energy? Only possible ans is that a quasar is an active black hole ie huge amounts of matter getting collapsed in a black hole…

These quasars are way to big to be formed by collapsed stars..so how do quasars form?

The leading theory is that when a gas cloud, that usually clumps together to form stars, clumps together at a very high rate, the center collapses under its own gravity (instead of igniting to form a star), ripping a hole in space resulting in a black hole…

So it looks like that Black Hole came first…

This is also supported by smaller galaxies like NH210, which have black hole, the size of Milky Way (one of largest galaxies, in the 90 percentile), which shows that black holes don’t evolve/grow with galaxies, but instead galaxies grow around them…

But how does a quasar turn into a galaxy? We see that in quasars, black holes spit out matter..this happens when a black hole eats too much too fast…and so it’s gravity cannot consume so much matter at a time, leading it to belch and spit out matter…

But how does this violently spit out matter trigger star formation? It doesn’t… we observe that this spit out matter actually goes to a neighboring stabler galaxy and forms stars there …

The black hole then gobbles up these smaller neighboring dwarf galaxies to become massive over time..

it is this devouring that gives Milky way it’s spiral shape..even today it’s devouring the saggitarious galaxy..it stands today at 200 Bil stars…

why is milky way not forming stars anymore? Coz, the black hole at the center is still very active and hence the core is very hot…gas cloud need to cool down to form new stars..

In 4 bil yrs we’ll collide with the Andromeda galaxy..stars are too small to collide with other stars, but the dust clouds at the center will collide and knock the stars off their orbits..the spiral shape will be no more ..new stars will form

How Elements are Made

ref: How the Universe Works S04E01 How the Universe Built …

  • Hydrogen: Basic building block from the Big Bang
  • Helium: Fusion in a star’s core due to gravity pressure and temp
  • Carbon, Silicon: Fusion of Helium atoms in the star’s core
  • Iron: Reaction of Carbon etc. but robs the star of the energy it needs to stay up causing the 1st gen star to go supernova ie explode
  • Copper: The 1st gen stars’ supernova leads to the creation of 2nd gen star that contains H and other heavy metals from the core of the 1st gen star. These 2nd gen stars form red giants where the iron atoms turn to copper by iron atoms absorbing neutrons that then undergo beta decay to become protons and release electrons
  • Gold, Lead,Iridium and other super heavy metals : These even higher mass elements are created by neutron star merger, which is when 2 neutron stars in a binary system collide
  • Lithuim: Li is a light metal, but it;s source is astonishing….it’s formed by cosmic rays ( atomic nuclei accelerated to speed of light by supernova explosion). When these high speed atomic nuclei collide with each other they form Li

But when the Earth formed 4 bil years ago, the heavy metals including iron and above got trapped in the core. The leftover iron and copper was dissolved in the ocean water. But when plants started photosynthesis, there was free oxygen in the air, that reacted with the leftover iron in the ocean water to form iron oxide that then sank to the ocean floor which we mine today.

The only unsolved mystery is of Iridium and other heavy metals,as the ones from 4 billion years ago are all concentrated in the earth’s core…Turns out that 65 mil years ago, an asteroid collided with the earth and wiped away the dinosaurs…this asteroid contained heavy metals like Iridium and it’s impact disintegrated it and covered the planet with a layer of heavy metals that later settled…the heavy metals that we mine today come from this layer formed 65 mil yrs ago from the asteroid that hit Yucatan Peninsula in Mexico…Other asteroid impacts have delivered Gold, Platinum,Nickel and other heavier elements

So it’s the ancient plants that enabled us to get iron, and it’s the remains of dead ancient plants that we use today as Oil and other hydrocarbons

Is Physics and Maths the same

The past and current mathematica theories strive to make sense of the physical world, but it’s known that Maths and Physical world are 2 separate things..Physical world is real and Maths is abstract approximation….every therory just aspires to be a better approximation of physics that came before it…equations are not things, they’re ideas…they don’t have velocity and mass…

But the current competing theories for the Theory of everything, namely String Theory and Loop Quantum Gravity proport to be exact theories of physics, not approximations…This means Physics will be reduced to pure maths..meaning that physical world arises out of maths equations..the equations somehow describe an exact non material reality that delivers, as a side effect, the physical universe…

string theory postulates that particles (that have mass and velocity) are nothing more than vibrational modes of primitive strings..the whole idea, like maths, is based on axioms…we don’t care what’s in the string, just that when it vibrates in a particular mode it represents a particular particle

Historically physics was experiments in lab and then write down maths that approximates the results of experiments in one way or another…

But with these 2 theories, they’ve flipped it around and say that we’ll just have logical axioms that give rise to physical reality

Consciousness and The Interface Theory of Perception, Donald Hoffman

NOTES:

  • In Evolutionary Game Theory, Interface approach beats reality perception every time…
  • Space time is species specific desktop, and objects are icons on it…
  • So asking if the objects are truth/real or not is the same mistake as asking if the file is really blue or rectangular….
  • Causality in physical world is also fictional, just as dragging the file icon on trash icon does not CAUSE the file to be deleted…SO CURRENT THINKING THAT NEURAL ACTIVITY MIGHT SOMEHOW CAUSE CONSCIOUSNESS ARE WRONG QUESTIONS…NO PHYSICAL OBJECT CAN HAVE ANY CAUSALITY, AS NO PHYSICAL OBJECT IS REAL…
  • Conscious Agent Thesis:
  •  CLAIMS
    • Conscious agents Comprise of:
      • W, X, G: Probability Spaces
      • P, D, A: Markov;s Kernels
      • N: integer
    • Every Conscious Entity and Activity can be modelled by Conscious agents
    • World consists of conscious agents ie real reality is just consciousness ie conscious agents in interaction
  • INFERENCES
    • Conscious Agent Networks (CAN) are Universal Turing Machines
    • Every CAN is a new CA
    • Current mind-body problem solutions assume that physics is fundamental and then try to explain how consciousness arises from it, but CA Theory assumes that Consciousness is fundamental and all of physics comes out of it…and it’s able to prove it mathematically, described in Conscious Realism Thesis, which when compared with physics of today, shows following one to one mappings in equations:
      • Asymptotic Dynamics of Subconscious Agents represent particles in our space time perception
      • states of the dynamics are equivalent to properties of particles
  • CHALLENGES
    • There are unconscious process like reflex actions, then how is consciousness fundamental?
      • I am unaware of your consciousness, but that doesn’t mean u’re unconsciousness,,,so my consciousness is not absolute….i’m unconscious to my reflexes, doesn’t mean they’re unconscious in the absolute sense..
    • Do we percieve reality or construct it within us
      • we do percieve outside reality, but not as it it, meaning that what we see as dog and cat and rock are our interaction with other CAs (ie conscious agents) but we don’t percieve it as such, and instead see icons on desktop ie cat and rock…
      • so space time and objects are all constructions in our mind by our perception, but it’s a response to our interactions with the conscious agents in the external world …
    • If everything is a CA, what’s animate(alive) or dead
      • Alive and Dead and Soft or hard or Fragrant are all a part of perception and so NOT REAL…on Q of what’s alive and what’s dead, our perception has evolved to be just enough to survive, and so at some point we give up and start to percieve unthreatning things like rocks as a part of the objective reality that we percieve and hence classify it as inanimate…