Most of the universe is missing, for example. The atoms we know about account for less than 5% of the mass of the observable universe - the rest is dark matter (around 25% of the mass of the universe) and dark energy (a whopping 70%). No one knows what either of these things actually is.
At the subatomic scale, we know there are three families of fundamental particles - called “generations” - and each one contains two quarks, a neutrino and a negatively charged particle (the lightest being the electron). But why are there three generations in the first place?
And the big one: why do the two pillars of 20th century physics, quantum mechanics and Albert Einstein’s general theory of relativity, not agree with each other?
In Weinstein’s theory, called Geometric Unity, he proposes a 14-dimensional “observerse” that has our familiar four-dimensional space-time continuum embedded within it. The interaction between the two is something like the relationship between the people in the stands and those on the pitch at a football stadium - the spectators (limited to their four-dimensional space) can see and are affected by the action on the pitch (representing all 14 dimensions) but are somewhat removed from it and cannot detect every detail.
In the mathematics of the observerse there is no missing dark matter. Weinstein explains that the mass only seems to be missing because of the “handedness” of our current understanding of the universe, the Standard Model ofparticle physics. This is the most complete mathematical description physicists have of the universe at the quantum level and describes 12 particles of matter (called leptons) and 12 force-carrying particles (called bosons), in addition to their antimatter partners.
Radical ideas that claim to solve all the problems of physics - so-called final theories of everything - have come and gone countless times in the history of physics and many are notable for emerging from outside the traditional world of university physics departments. In 2007, physicist and surferGarrett Lisimade headlines when he claimed to have founda way to unify physics. Lisi’s ideas never took off, because his theories did not make enough predictions that could be tested in experiments, the hallmark of a good scientific idea.