Air has a density of about 1.3 kg/m³. From Carbon aerogels by Marcus A. Worsley and Theodore F. Baumann: ..though silica aerogels held the title of "world's lightest material" for a long time at ~1 mg/cm³, recently, carbon-based aerogels have shattered that record with a density of less than 200...

I have found contradictory information about this. Does the Higgs field give mass only to the $W^+$, $W^-$, and $Z^0$ bosons or does it give mass to other particles as well?

In this question when I solve for time I get $t=-1$ & $t=5$. What does it actually mean at $t=-1$?

I am very confused by the statement made in Haag's, Local Quantum Physics: Fields, Particles, Algebras (page 46): ... the idea that to each particle there is a corresponding field and to each field a corresponding particle has also been misleading and served to veil essential aspects. The rôle o...

In standard quantum mechanics, the wave function have discrete energy-values due to a potential. However, my very limited understanding of QFT is that electrons are excitation in the Dirac field, and the number of electrons is discrete even in free space. What is the reason for this, and why is t...

Sir $P=F/A$ And since $F$ and $A$ both are vectors but $P$ is scalar. So doesn't it violates that "Division is NOT defined for vectors"?