Cosmology Lecture 06

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The Bright Side, continued

Failed to parse (unknown function "\begin{matrix}"): {\displaystyle \begin{matrix} Gauge\ Bosons & spin & charge & mass \\ \gamma & 1 & 0 & 0 & (carries\ electroweak\ force) \\ w^\pm & 1 & \pm 1 & 80.4 GeV & (carries\ electroweak\ force) \\ Z^0 & 1 & 0 & 91.2 GeV & (carries\ electroweak\ force) \\ gluons & 1 & 0 & don’t\ know & (carries\ strong\ force) \\ Higgs & 0 & 0 & >114.4GeV \\ graviton & 2 & 0 & 0 \\ \end{matrix} \,\!}

Useful Scales/Conversion tricks

In particle physics, , because (which had units ). In condensed matter physics, .

The Planck mass is the mass scale at which the effect of gravity and quantum effects are comparable. We can get an estimate of the Planck mass by setting the Schwarzschild radius () equal to the Compton wavelength of a particle (). Dropping our constants (2’s, ’s), we get:

Another number of interest is the energy density in . We know

Converting to , we get: