I see 4 lines on there, one for elementary particles, one for black holes, one for things made of ordinary matter (atoms up to suns) and another for dark matter bound objects (globular clusters,...
I see 4 lines on there, one for elementary particles, one for black holes, one for things made of ordinary matter (atoms up to suns) and another for dark matter bound objects (globular clusters, galaxies, etc.). Neutron stars are in a class by themselves.
You just have to admire a chart that casually purports to show every single thing in the Universe in one simple 2D plot.
The chart in question is from a piece in the most recent issue of the American Journal of Physics with the understated title of "All objects and some questions".
Know more...about the 2D plot
We plot all the composite objects in the Universe: protons, atoms, life forms, asteroids, moons, planets, stars, galaxies, galaxy clusters, giant voids, and the Universe itself.
Humans are represented by a mass of 70 kg and a radius of 50 cm (we assume sphericity), while whales are represented by a mass of 10^5 kg and a radius of 7 m.
The "sub-Planckian unknown" and "forbidden by gravity" sections of the chart makes the "quantum uncertainty" section seem downright normal — the paper collectively calls these "unphysical regions". Lovely turns of phrase all.
But what does it all mean? My physics is too rusty to say, but I thought one of the authors' conjectures was particularly intriguing:
"Our plot of all objects also seems to suggest that the Universe is a black hole."
Huh, cool.
Summary from the published study
We present an overview of the thermal history of the Universe and the sequence of objects (e.g., protons, planets, and galaxies) that condensed out of the background as the Universe expanded and cooled. We plot (i) the density and temperature of the Universe as a function of time and (ii) the masses and sizes of all objects in the Universe.
These comprehensive pedagogical plots draw attention to the triangular regions forbidden by general relativity and quantum uncertainty and help navigate the relationship between gravity and quantum mechanics.
How can we interpret their intersection at the smallest possible objects: Planck-mass black holes (“instantons”)? Does their Planck density and Planck temperature make them good candidates for the initial conditions of the Universe?
Our plot of all objects also seems to suggest that the Universe is a black hole. We explain how this depends on the unlikely assumption that our Universe is surrounded by zero density Minkowski space
I see 4 lines on there, one for elementary particles, one for black holes, one for things made of ordinary matter (atoms up to suns) and another for dark matter bound objects (globular clusters, galaxies, etc.). Neutron stars are in a class by themselves.
Jason Kottke
Know more...about the 2D plot