Black hole P1: mass vs matter vs weight

August 25, 2017

This is the series of post I’m writing to understand what by black hole people mean .

  1. Mass, matter weight …
  2. Gravity
  3. I’ll try to understand what space-time really mean(according to einstein theory)
  4. What people really mean by black holes(according to my understanding).

Let’s start with part 1

Matter :

  • So everything we see around us is matter. Solid/liquid/gas is made of something(what it is that something, we can discuss it later), that thing/stuff is called matter.
  • In modern physics, matter is not a fundamental concept because a definition of it is elusivewikipedia

Mass :

  • So as we said, everything is made of matter(something), to quantify that thing mass is used.
  • Mass is a property of a physical body.
    • We take that every physical body has property called mass.
    • ^We assume it and take if fundamental property like charge on electron to define everything around it.
    • The mass of an object determines its acceleration in the presence of an applied force similar to ‘charge in electro-magnetic field’.
    • It’s similar to charge in electro-dynamics, the basic property. Refer: basic concepts on electricity
  • In Newtonian physics, mass is term for describing the amount of matter object has.
  • It is different than weight.

If you go deep down, there are still theories being made. link has lot more info about it.

  • According to special relativity:
    • there are two types of mass defined, they are rest mass and relativistic mass.
    • The mass of an object doesn’t remain constant throughout a movement.
    • The rest mass is the mass measured when the object is at rest.
    • The relativistic mass(which increases with velocity) is measured for a moving object.
    • These two are nearly the same for speeds much less than the speed of light, but varies greatly when the speed approaches the speed of light. The rest mass of the electromagnetic waves is zero
  • According to general relativity(GR):
    • According to wiki introduction:

      The concept of mass in general relativity (GR) is more complex than the concept of mass in special relativity. In fact, general relativity does not offer a single definition of the term mass, but offers several different definitions that are applicable under different circumstances. Under some circumstances, the mass of a system in general relativity may not even be defined.

    • has lot of info to parse, left to reader if he wants to go rabbit hole.
  • There is a youtube video whose transcript might also give a theory which sounds plausible.
    • 99% of mass of proton is in vibrational energy of quarks and binding energy of gluon field. The actual intrinsic mass of quarks is a tiny contribution. Quarks vibrate in gluon field and this vibrating quarks has some potential energy(Potential energy is like those quarks have it has potential to do it, when time come or this guy has lots of potential, when time/force comes this will be converted to some energy).
    • The electron and quarks get their tiny masses from a confinement via the Higgs field( It’s assumed that everywhere in universe has the common field call higgs field, and some particle can move freely in these field and some can’t. So there ability to move through this field determines their mass. If particle can easily move then it has low mass and and particle that can’t move freely it has higher mass ). He further says, if we remove the field the particle will be massless speed of light particle.
    • It looks like everything that with mass is composed of massless, light speed particle that are prevented from moving freely through universe, as well as the fields that confine those particle.
    • So mass is really not a fundamental property, Is it just a result of massless particle and field bumping around resisting acceleration ?
      • Yes it kind of is, this acceleration resisting mass, intertial mass seems to be emergent property of ensemble(a group of items viewed as a whole rather than individually).
      • Then he goes with relation of mass and gravity …

So as we have seen basic property like mass has still not been figured out, people are still understand what mass is. Theory’s are proposed, hacks are made and we are progressing.

Weight : Weight is the force your mass exerts in gravity.

  • Basic formula is : Weight = mass * gravity.
  • Weight is measured in Newton(N or kg-m/s2)
    • 1 newton of force is the force required to accelerate an object with a mass of 1 kg with 1 m/s2)


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