Life and death of stars
Accreting mass due to gravity simulation
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- What we have here is a simulation created
- by Peter Collingridge
- in response to one of our computer science challenges
- so, how many particles might interact gravitationally
- and the whole point of this is to get an intuition
- for how galaxies form, why they have
- the structures they have
- why solar - how solar systems form and how
- they have the structures they have and how
- gravity alone can kind of define that structure
- and what's really interesting about the simulation
- besides the fact that it's just mesmerizing
- and extremely cool
- where it shows the particles collide, get
- once they get to a certain critical mass
- -you see that they get colored yellow-
- maybe to indicate that they
- are now a star
- -fusion can now occur-
- and you can zoom in at different levels
- to really see how the different particles
- , the different masses are interacting
- and you can actually rotate
- you can actually rotate
- that to see a little bit clearer
- this is kind of looking
- kind of right on top of it
- to see how they are interacting
- It's a three dimensional simulation
- so it's a very rich way
- of thinking about these
- And what's exciting for me
- it's highly dependent on what the initial
- conditions are
- and in an earlier version
- of Peter's simulation
- he did not give
- eh...give a net angular momentum
- to the system
- and so you do not have as
- as much of, kind of the planet- satellite
- or as much of the disc structures forming
- although right here,
- there does seem to be a dominant plane
- in this scenario
- and, what's exciting is, here
- we have a binary system
- sometimes you restart it
- you might not have a binary system
- depending on the initial conditions
- you might have something that starts
- to look like the Milky Way
- sometimes you might have something that
- looks very different than the Milky Way
- and it really gives us clues
- of why we see
- such diversity, specially in...when
- we're looking at galaxies
- the structure of galaxies, that is
- highly dependent on initial conditions
- One can argue that our own solar
- system did have some net
- initial angular momentum
- because the current theory, it was...
- -what really canalized nearby supernova,
- that sent a shockwave and
- allowed the dust that would form
- our Solar System to reach a
- critical mass and start to
- condense into the Sun and the planets
- and so, this isn't, in my mind,
- a too unrealistic of a scenario
- and it's really cool to look at
- and it really gives you a sense of thing
- you already see a binary star
- orbiting around each other
- or orbiting around the center of mass
- which kind of looks like
- around each other
- and then this star right over here has
- it's own kind of captive planet
- that it's just rotating around it
- you can see it a little bit clearer
- if we had a very, at least
- from this perspective, a very close range
- we cann zoom in a little bit more
- to see it a little bit better
- this has a satellite but
- then they are also kind of dancing
- around each other
- So it's a really fascinating, a really
- fascinating simulation, I can really
- stare at this and play with it
- for days
- and I encourage you to
- play with it, restart it, see how
- the initial conditions or
- what type of solar systems or
- galaxies you might end up with
- or wether they form discs,
- wether you habe binary systems or not
- and if you have planets with satellites
- And then, if you are more advanced,
- actually play with the code
- and see if you can
- really change the initial conditions,
- the starting velocities of things
- the number of particles of things
- the distribution of mass
- that you start off with,
- the angular momentum that
- you start off with
- and see how that might change
- the structure of the universe
- that you create, and an anotation
- to this video that links directly
- to this simulation; and I'll also
- put the link inside of the description
- So: have fun; I can literally spend hours
- with this, it is fascinating, fascinating module
- that he's created,
- we zoom in and out and I really thank
- Peter Collingridge for this
- incredible contribution.
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At 5:31, how is the moon large enough to block the sun? Isn't the sun way larger?
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