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I like Markus' write up.

In the summary, what does "planned future accelerators" refer to?
HL-LHC (ILC?, 100 TeV?) If it also includes 100 TeV (or around
similar energies), perhaps we  should use a world somewhat stronger
than "potentially", since I think 100 TeV can cover a lot of ground in
the model space (and significantly more than others).

Liantao

On Fri, Oct 11, 2013 at 12:57 AM, Markus A. Luty
<[log in to unmask]> wrote:
> The first installment of my homework: here is my suggestion for what is now
> lines 31-41 of the 5-page summary. It is longer than what is there now, but
> I think these may be the most important lines in the document.
>
> The discovery of the Higgs particle establishes that the masses of
> elementary
> particles arise dominantly from interactions with the Higgs field that is
> turned
> on throughout the universe. We now have for the first time in the history of
> particle physics a theory all of whose ingredients have been experimentally
> verified, and that can be consistently extrapolated to energy scales many
> orders
> of magnitude above the energy scale of collider experiments. This historic
> achievement is not an end, but a beginning, because the standard model of
> particle physics leaves many fundamental questions unanswered. In the
> tradition
> of bold theoretical ideas such as the Higgs mechanism (recognized by this
> years'
> Nobel prize) particle physicists have proposed compelling ideas that address
> these important questions, and that have their crucial test at the TeV
> scale:
>
> * The fact that the observed Higgs particle is a scalar particle makes it
> very
> difficult to understand why its mass scale is smaller than much-larger
> fundamental mass scales such as the Planck scale. Addressing this problem
> requires significant additional structure: either supersymmetry (an
> extension of
> Einstein's spacetime symmetry), Higgs compositeness, or extra dimensions of
> space. All of these ideas predict a rich spectrum of particles at the TeV
> mass scale,
> typically including a larger Higgs sector.
>
> * The standard model does not account for the dark matter that makes up most
> of
> the matter of the universe. A stable particle at the Higgs mass scale with
> weak
> interactions with ordinary matter (a WIMP) is one of the simplest and
> compelling
> theories of dark matter. If dark matter is a WIMP it  may be possible to
> study
> dark matter under controlled laboratory conditions in collider experiments.
>
> To summarize: \emph{Compelling ideas about fundamental physics predict new
> particles at the TeV energy scale that are potentially accessible to present
> and
> planned future accelerators. These experiments are the crucial tests of
> these ideas.
> Furthermore, if such particles are discovered, they can be studied in detail
> to
> determine their properties, leading to the establishment of new fundamental
> laws of
> nature.}
>
> The past successes of particle physics clearly call for us to continue and
> extend a three-pronged program of research in collider experiments:
>
> First, we must study the Higgs boson itself in as much detail as possible,
> searching for signs of a larger Higgs sector and the effects of new heavy
> particles.
>
> Second, we must search for small deviations in the standard model
> predictions
> for the couplings of the Higgs, W, Z, and top quark from new particles.
>
> Finally, we must directly search for new particles with TeV masses that can
> address important problems in fundamental physics.
>
> Markus Luty
>
> ============================================
> Physics Department
> University of California, Davis
> One Shields Avenue
> Davis, CA 95616
>
> Phone: +1 530 554 1280
> Skype: markus_luty
>
>
>
> On Thu, Oct 10, 2013 at 1:57 PM, Ashutosh Kotwal <[log in to unmask]>
> wrote:
>>
>> On Oct 10, 2013, at 4:03 PM, "Peskin, Michael E."
>> <[log in to unmask]> wrote:
>>
>> > minutes of the EF phone meeting  10/8
>> >
>> > attending:  Chip, Michael, Sally, Daniel, LianTao, Ashutosh, Cecilia,
>> > Reinhard, Markus, Andy White
>> >
>> > There are many items in these minutes that all of you need act on more
>> > or less immediately. Please read these minutes carefully.  We summary the
>> > action items at the end.
>> >
>> > Our reports are overdue.  We would like to send our reports to the
>> > Snowmass conveners on Tuesday, October 15.
>> >
>> > All line numbers refer to the 10-3 versions sent out last Friday.
>> >
>> > 1.  From the group on the phone, and from the emails that we have
>> > received, you seem to be happy with the reports that we put together except
>> > for some specific points discussed below.  Michael emphasized that, if you
>> > are not happy, you must speak up now.  This is best done by sending email to
>> > snowmass-ef.  Urgently, please.
>> >
>> > 2.  Many of the people on the phone were uncomfortable with the language
>> > on likes 40-41 of the short report:  "These puzzles imply that new particles
>> > with masses of the order of 1 TeV which resolve these questions will be
>> > found -- and will be accessible to existing and planned accelerators."
>> > They felt that "imply" was too strong and that the implication of 1 TeV
>> > rather than, say, 5 TeV was made in this sentence.
>>
>>
>> what about replacing
>>
>> "…masses of the order of 1 TeV"
>>
>> by
>>
>> "...masses below about 10 TeV"
>>
>> just as an example, ATLAS studies have shown sensitivity to KK gluons ->
>> ttbar in the 5 TeV range
>>
>> ------
>>
>> as far as the word "imply" goes, it seems to me that "imply" has a
>> built-in caveat that it is an implication on the basis of a certain logic.
>> In this case, the logic is that nature will avoid too much fine tuning. The
>> 10 TeV number would make the fine tuning about 0.01%
>> and the logic is that this is very uncomfortable amount of fine tuning
>>
>> So, I  think we are protected in the legalistic sense if we do use the
>> word "imply"
>>
>> Also, to me, the scale of how "strong" the language is, is no longer set
>> by the "strength" of "there must be some new physics to explain massive
>> gauge bosons…"  which worked very well for SSC and LHC motivation. I don't
>> think we have to normalize to that any more. I think we have to normalize to
>> the "strongest" language we could use for ANY new physics, in the post-Higgs
>> discovery, post-theta13, post-Planck…etc…  world we live in now.
>>
>> regards,
>> Ashutosh
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>
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