456
E. Rabinovici
quantum mechanics were discovered remained non-conservative throughout their
life. Some of the latter developed eventually such adventurous ideas as to form
as a reaction a much more conservative following generation. The conservative
generation perfected the inherited tools and has uncovered and constructed the
Standard Model. They themselves were followed by a less conservative generation.
The new generation was presented with a seemingly complete description of the
known forces. In order to go outside the severe constraints of the Standard Model
the new generation has drawn upon some of the more adventurous ideas of the older
generation as well as created it own ideas. In a way almost all accepted notions were
challenged. In the past such an attitude has led to major discoveries such as relativity
and quantum mechanics. In some cases it was carried too far, the discovery of the
neutrino was initially missed as energy conservation was temporarily given up.
The standard model is overall a very significant scientific achievement. It is a
rather concise framework encompassing all the known properties of the known basic
interactions. It is arguably the most impressive theoretical understanding of a large
body of experimental information existing. An understanding backed by precise
predictions all verified by high quality experiments. In this context it may seem
surprising that one is searching for anything beyond the Standard Model. There are
however diverse scientific reasons for the search of the beyond.
In 2007 the scientific community was aware of quite a few gaps in the
understanding of the particle interactions. One class of observations posed obvious
pressing problems:
• There is a large body of evidence that the so called dark matter should be
composed mostly of different particle(s) than those that serve as the building
blocks of the standard model. What are they? More recently also what is called a
dark energy was needed to explain the data. Its possible origin(s) is under active
study.
• A standard model for cosmology is forming and it includes in most cases
versions of inflation. Such models seem to require the existence of a new heavy
particle(s). What are they? On a more speculative note, models require more
detailed understanding of how physical systems behave in big bang/crunch like
circumstances and of how and if universes may form.
Another set of observations could be either defined as posing problems requiring
an explanation or as pointing to new directions only after being combined with a
certain amount of theoretical prejudice (TP). In the past some major advances were
driven by such combinations.
• Three known interactions, the colored, the weak and the electromagnetic interactions all obey the dictum of quantum mechanics and are all well described by
gauge theories but have otherwise very different properties and strengths at the
energy scales probed till 2007. A TP, a strong and deeply ingrained one, suggests
that all interactions, those known and those yet to be discovered should unify
at a certain higher energy scale. This is the idea of a Grand Unified Theories
(GUTS). Eventually it was found that to realize a particular aspect of this, the
E. Rabinovici
quantum mechanics were discovered remained non-conservative throughout their
life. Some of the latter developed eventually such adventurous ideas as to form
as a reaction a much more conservative following generation. The conservative
generation perfected the inherited tools and has uncovered and constructed the
Standard Model. They themselves were followed by a less conservative generation.
The new generation was presented with a seemingly complete description of the
known forces. In order to go outside the severe constraints of the Standard Model
the new generation has drawn upon some of the more adventurous ideas of the older
generation as well as created it own ideas. In a way almost all accepted notions were
challenged. In the past such an attitude has led to major discoveries such as relativity
and quantum mechanics. In some cases it was carried too far, the discovery of the
neutrino was initially missed as energy conservation was temporarily given up.
The standard model is overall a very significant scientific achievement. It is a
rather concise framework encompassing all the known properties of the known basic
interactions. It is arguably the most impressive theoretical understanding of a large
body of experimental information existing. An understanding backed by precise
predictions all verified by high quality experiments. In this context it may seem
surprising that one is searching for anything beyond the Standard Model. There are
however diverse scientific reasons for the search of the beyond.
In 2007 the scientific community was aware of quite a few gaps in the
understanding of the particle interactions. One class of observations posed obvious
pressing problems:
• There is a large body of evidence that the so called dark matter should be
composed mostly of different particle(s) than those that serve as the building
blocks of the standard model. What are they? More recently also what is called a
dark energy was needed to explain the data. Its possible origin(s) is under active
study.
• A standard model for cosmology is forming and it includes in most cases
versions of inflation. Such models seem to require the existence of a new heavy
particle(s). What are they? On a more speculative note, models require more
detailed understanding of how physical systems behave in big bang/crunch like
circumstances and of how and if universes may form.
Another set of observations could be either defined as posing problems requiring
an explanation or as pointing to new directions only after being combined with a
certain amount of theoretical prejudice (TP). In the past some major advances were
driven by such combinations.
• Three known interactions, the colored, the weak and the electromagnetic interactions all obey the dictum of quantum mechanics and are all well described by
gauge theories but have otherwise very different properties and strengths at the
energy scales probed till 2007. A TP, a strong and deeply ingrained one, suggests
that all interactions, those known and those yet to be discovered should unify
at a certain higher energy scale. This is the idea of a Grand Unified Theories
(GUTS). Eventually it was found that to realize a particular aspect of this, the