# Chit Chat re: Quantum Physics

• Sep 7, 2014 · 4:00 PM
• This location is no longer available

We will be discussing Einstein's Special Relativity and showing the videos "Relativity - Chapter 1 of 6" through "Relativity - Chapter 4 of 6."  Here is the link:

• ##### Mitchell W.

ALBERT EINSTEIN'S SOLAR ECLIPSE MEASUREMENTS IN 1921 verified spacetime curvature.Of course the measuring device is part of what's being measured so the space between the device and the planet or star in question is skewed

1 · September 13, 2014

• ##### A former member

One example of many where a physical prediction arose from an insistence upon mathematical consistency, and experimental support had to wait for engineering technology to catch up!

September 15, 2014

• ##### Mitchell W.

My new kindle e book "TheEquation of Everything" does not use string theory in formulating a hypothesis that unifies QuantumMechanics and Relativity.I was shocked that eventhough I explained string theory in the brief book I didn't need it for the math.

September 11, 2014

• ##### Andy

To try a high-level approach Mark's original question ("I just can't wrap my head around what curved space-time really means"), let me say that I have tried it this way: As an alternative, and equivalent, way of saying space-time is curved, we can say that the equation to measure distance is not the same everywhere. When we look at it that way, space-time is nothing special, but measuring distance in it is complicated.

When I say "I tried understanding it that way", I mean that I once asked a relativity expert (Lawrence Krauss, actually) if that was a legitimate way of understanding it, if it was truly equivalent to calling space-time curved. He said no. So, sadly, my suggestion probably won't get you very far with real physicists. But maybe it helps a little bit, at a high level?

September 12, 2014

• ##### A former member

Well, I'm going to have to respectfully disagree with Dr. Krauss here. After all, the only way we can tell spacetime is curved is by measuring its effects, and the only way we can quantify those effects is with mathematical equations. So I'd be interested in knowing, I guess, what Dr. Krauss thinks the alternatives are.

September 13, 2014

• ##### Mitchell W.

Gravity results from space being curved by mass.Space must contain some energy or matter or it may collapse on itself in a "Big Crunch".If mass curves space does space cause reciprocal curvature of mass?In a black hole space approaches infinite curvature as a point and therefore the mass would approach reciprocal curvature which approaches but doesn't reach infinite curvature as the center of a vortex would.

1 · September 12, 2014

• ##### Mitchell W.

One more comment a tensor of the fourth degree representing the curvature metric of inertial mass on Spacetime is the metric of the mass of a quanta(quantum)Rab represented by the tensor of the fourth degree acting on R g ab by g ab where g ab is the metric of gravity exerted by gravitons on de sitter space from quanta.

September 11, 2014

• ##### Mitchell W.

One other point in quantum mechanics de sitter anti de sitter and Hilbert space can be as small as Planck length 10-33 cm and still be curved by the mass of a quanta or Planck's Mass which is(hc/8piG)1/2.Using this for R ab and the gravitational coupling constant between two quanta you can get R g ab from Einstein's equation of Relativistic Gravity or 8 pi T ab=R ab-1/2 R g ab as R ab is known and the stress energy tensor T a b can be derived from R ab vs R ba where Planck's mass is used for R ab and the gravitational coupling constant between two quanta of Planck mass is one.So the Spacetime curvature variant R g ab can be calculated for Planck mass.This may be digressing from the topic but the question was asked how Spacetime is curved .

September 11, 2014

• ##### Mitchell W.

By the way the Spacetime curvature variant for the metric g ab whose inertial mass is related to R ab is R g ab in the action formula S=-1/2k2(-g ab)1/2 R g ab.k is the gravitational coupling constant.I felt the action formula of the metric needed more clarification and S is the most likely action or behavior of the metric g ab.

September 11, 2014

• ##### Mitchell W.

Mass curves Spacetime using gravitons

September 11, 2014

• ##### Mitchell W.

The amount if curvature depend on the mass acting on Spacetime that's doing the curving .Black holes curve Spacetime down to a point like a collapsing cone from the extreme mass collapsed in the black hole.A near vacuum causes Spacetime to be almost flat due to the lack of mass doing the curving

September 11, 2014

• ##### Mitchell W.

Gravity is the curvature of Spacetime Rgab for the inertial mass of Rab and metric g ab

September 11, 2014

• ##### Mitchell W.

Spacetime is curved mathematically according to the action formula S(action)=-1/2k2(-g)1/2 R where R is the Spacetime curvature metric of any metric g whose mass is described by R ab and whose most likely action or S equals the expression

September 11, 2014

• ##### Mitchell W.

Handling quantum and classical physics as one.

September 11, 2014

• ##### Katherine B.

Mitch,
What observation are you referring to that is nice?

September 11, 2014

• ##### Mitchell W.

Nice observation but the Newtonian definition of gravity may not be true as Einstein stated it was an effect of Spacetime curvature caused by mass

September 11, 2014

• ##### Katherine B.

Hi John,
I like the topic. I'd like to hear what a few others who have prepared a bit to have a say and the rest of us to ask questions and get feedback. This would give a variety to the topic. It's also an opportunity for some to try out their ideas and get some feedback from the audience. A 5 to 10 minute presentation and then questions to clarify and then a discussion. For instance, I would look forward to hearing Mitch who has a lot to say but is hard for some of us to follow. Also someone who has a handle on quantum and classical physics as a unity rather than 2 separate sciences. I am now researching on Ernst Mach and absolute rotation. I could say a few words about it. No video unless it illustrates or describes a particular event - like the particle-wave phenomena. Otherwise video can't engage our minds or imaginations like interesting ideas can.

September 10, 2014

• ##### A former member

"Quantum and classical physics as a unity rather than 2 separate sciences" yes! Exactly! There's too much mysticism (e.g. the entire ridiculous "Copenhagen interpretation") and not nearly enough apprehension of the continuous GENERALIZATION that has taken place from Newton to Lagrange to Hamilton and Jacobi to Clerk Maxwell to Boltzmann to Einstein to Dirac. Addressing this is an explicit goal of the Mathematical Physics Study Group, which I will relaunch after my presentation at this month's Strange Loop conference.

September 11, 2014

• ##### Katherine B.

Hi John,
It's good of you and Julian to step up to a vacuum. It would be good to be more inclusive to all voices. Every time you are at least not open to what others have to say and dismiss their objection as not being what some people voted on, you are excluding their participation. There are other ways besides showing videos from which everybody would benefit. It wouldn't hurt to allow those. When you show a video you choose not to do something else. It's just the "something else" that could benefit all of us.

September 10, 2014

• ##### A former member

Hi Katherine,
To talk about something concrete, for the next meeting the group decided last time to continue on Special/General Relativity, Minkowski space and the connection between magnetic fields and relativity, etc. How would you like to see the topic handled, including video viewing/presentations/re­ading material, etc, both before and during the meeting. That is, outline how you would like to see the topic (or any topic) covered for the two hours of the meeting, what will be the best way (as you see it) for willing participants to prepare themselves, how questions should be answered, and so on. The assumption is that they will be NO outside authority with special expertise, beyond the expertise of the members of the group. If you do not like or agree with the topic tell us what you would like us to do instead during the October meeting.

1 · September 10, 2014

• ##### A former member

I mentioned before that I knew of at least three people with objections to showing videos and two with very strong objections have spoken here and have done the same in the past. Let me answer and not necessarily disagree with some of what has been said.
a) I will love to have Vanessa run the meetings, they go far smoother when she is around. However, she had been travelling for several months in the past and she plans to travel again in the (near?) future.
b) As far as dominating the conversation, if someone is presenting a topic there will be at least this person dominating the conversation. It happened with Dr. Sheldon Smith and with presentations by individuals about the Standard Model, Black Body radiation and other topics, before we decided to show videos. (continued below)

September 9, 2014

• ##### A former member

(continued)
c) The video option (either showing them or simply suggesting them) was decided because this being mainly a lay person's group there were serious problems and omissions during some past presentations. The decision to use videos coincided with the start of Vanessa's trip to Asia and with her agreement.
d) I do not have a vested interest in showing videos. On the contrary it has been a pain to download them, translate their format so that can be played on my Vista laptop and carry all the equipment to the meeting. However, others have voted in the past(as I repeatedly mentioned) to show videos. Maybe a poll should be in order.

September 9, 2014

• ##### A former member

Hello, I enjoyed the last meeting, thank you so much Vanessa. I would like to see if we can get Professor Andrew Cleland, from U.C. Santa Barbara to speak. I am willing to pitch in, to provide the professor, travel transportation since he is 1 hour and 30 mins away driving distance from Santa Monica. Here is more information: http://www.youtube.com/watch?v=qmGIb2oxo4M

Here is his contact information:
http://web.physics.ucsb.edu/~clelandgroup/cleland.html

Does anyone else nominate this professor as our guest speaker?

July 28, 2014

• ##### Katherine B.

Not a good idea to start charging for speakers. Could you or somebody else - including me - contact him and ask him to come and speak?

September 9, 2014

• ##### A former member

The former member that proposed this was Jose and he left the group in August. If you want to contact the professor and convince him to drive from Santa Barbara to Santa Monica, I doubt anyone in our group would object. At this point however we do not even have a date for any future meeting.

September 9, 2014

• ##### Katherine B.

I find several problems with showing too much video. When Vanessa was leading she never showed too much video. We all learn during discussion. When Vanessa isn't there leadership is never passed around but dominated, largely because of the video presentation, by much too few members. It takes me an hour to drive one way to Santa Monica and another hour to drive home. It simply isn't worth the time and trouble to make the drive to sit still and watch a video - even for an 30 minutes. I have many questions about quantum physics and enjoy the give and take of discussion by a very diverse group of people.

September 9, 2014

• ##### A former member

There still seems to be some confusion about my issue with watching videos, so let me please try to clarify:

I like the videos! I just like them on my 42" LCD TV through my FIOS connection at home! :-)

John says conversation topics petered out, so the group used the time to watch another video. To me, that indicates a problem, not a solution. Part of the point of watching videos beforehand is so we can all come better armed with discussion topics and questions, and really maximize the value of our face-to-face time.

That said, for some people, even watching videos together qualifies as a social activity. Others, though, have solved the video problem by coming to the Meetup "late" so as to have the conversation without watching the videos (again, perhaps).

Should we formalize that? Institute a hard limit of an hour for videos, then an hour for discussion? That would be my (very strong) preference.

September 9, 2014

• ##### A former member

There is no confusion in what you want. You have expressed your views clearly here and in past meeting comments and through emails: Your preference is not to show videos during the meetings. My answer (1) from before was in response to your observation about "questionable equipment and more than questionable internet connection." To summarize, we now have a reliable way of showing videos during the meeting, IF WE CHOOSE TO DO SO. My answer (2) also from before, was that past polls indicate that the majority wanted to present videos during the meeting. And polling also showed that some did not have or could not make the time to watch videos at home, which has been compounded by the fact that we have waited until the last moment to select and advertise the meeting topic and find the videos.

You may come late if you so choose, to avoid any videos but whether there is a hard video time limit or not, you may miss any potential discussion that may take place between video segments.

September 9, 2014

• ##### A former member

John, I'm glad it's clear to you. :-) I agree that it's unfortunate that we seem to struggle to identify topics and get them in front of the participants in a timely manner. Regarding missing conversation between segments, what I'm suggesting is that there not be any. That way, those of us who don't find value in watching videos in this setting can come at a well-defined time to participate in the discussion. Honestly, I'm baffled by what seems to me to be a rather dogmatic insistence that we continue to follow this loosely-defined structure that involves sitting around watching videos (and here I confess my strong reaction to "people don't have time to watch them at home;" if you don't have time to watch the material before coming to the Meetup, I question whether you have time for the Meetup). I'm asking for a compromise: watch, just please let the rest of us know when you'll be done so we can join at that point. I really don't think that's asking too much.

September 9, 2014

• ##### Howard G.

Opps, I wish to add that I also like people in the group doing presentations.

September 8, 2014

• ##### A former member

Once https://thestrangeloop...­ is behind me, I'd like to re-kick-off the Mathematical Physics Study Group, and would love to do a presentation about it.

September 9, 2014

• ##### Kate

I’m for either way, but I very much like the contributions made by the people who don’t like coming to watch videos. Considering we are on many levels of ability to reference, understand and articulate well, I want to accommodate those I’ve learned so much from. I recall past meetings where we watched videos from home and came prepared. It gives time for reflection and possibly better discussions. It seems an easy compromise so all of us might want to participate.

1 · September 8, 2014

• ##### Mitchell W.

I still like the videos even if it isn't new material for me as it show how to take complex concepts and put them in terms which are easy to understand. Dr.Michio Kaku was able to bridge this but I've been told that to reach the average Joe without a physics degree or one in advanced mathematics I need to present information in easier to understand terms.

September 8, 2014

• ##### Howard G.

I enjoy the videos

September 8, 2014

• ##### A former member

Sorry everyone, but I saw the topic, which is great (Special Relativity-yay!) but once again the group will be sitting and trying to watch YouTube videos on questionable equipment with more-than-questionable internet connectivity! At the risk of being anti-social, can I ask why we keep doing this? If there are YouTube videos to watch, can we not watch them at home prior to the meeting, then use the meeting time for what face-to-face is best for: discussion? I'd really like to meet and discuss physics. I just can't justify driving to Santa Monica to watch YouTube videos.

September 7, 2014

• ##### A former member

(1) During the last few meetings the video presentations have been downloaded before hand and reliably, loudly and clearly presented with no need for Internet access. And today, after about one hour, we ran out of topics to discuss and used the remaining time to show one additional video, not in the original list of videos. I typically make an effort to keep the cumulative video presentations to no more than 30 minutes; this leaves about 1:30 hours for discussion, more than enough time before we get to off the wall, "how many angels fit on the head of a pin" discussion.(2) I understand there are at least three people with mild to strong objections to showing videos during the meeting. However, during past polls the majority of attendees voted to present videos during the meeting and also several did not make or have the time to watch the previously advertised videos before hand.

September 8, 2014

• ##### Julian K.

Amazing and rewarding to be reminded in our discussion that even "Classical relativity" (pre-Einstien) as well as basic Special Relativity (Einstein, 1905), more than a century later, still involve some challenging and mind stretching concepts about the fundamental nature of the reality of which we are all an inherent part. I also think that the videos were an important aid in supporting and stimulating our discussion, as well in better "grounding" our comments, questions . . . and yes, even our speculations.

September 7, 2014

• ##### A former member

I don't object to watching videos... only to doing so during group time! Anyway, it's definitely good to be reminded that the technical term for the claim that relativity "overthrew" classical mechanics and quantum mechanics "overthrew" relativity is: wrong. :-)

1 · September 8, 2014

• ##### Michael

Coincidentally I am doing some work this minute with the triangle inequality and it reminds of of what Mitch was saying about light tending to take the shortest path. I know nothing of the math in regards to QM but I'm curious if anyone else knows of a good place to read how this plays into QM on a math level.

September 7, 2014

• ##### A former member

Hi Michael, there is a mathematical physics study group that I started but have had to take a personal hiatus from to focus on my presentation at the Strange Loop conference this month. Once the conference is over, I'll try to reinvigorate that (I haven't seen any activity in the group since my hiatus, unfortunately, even though it's very much intended to be individually driven).

1 · September 8, 2014

• ##### Mitch

Michael: It has been a long time, but I think Feynman covers that in his lectures on QED. Instead of talking about a photon's phase, he uses the analogy of each one having it's own stopwatch. Photons coming along the shortest path(s) all take the same time, so photons taking those paths end up with their stop watches pointing the same way ("in phase") and reinforce each other. Photons coming from other directions take many paths of varying amounts time, showing up with stopwatch hands pointing in all directions and largely canceling each other out. (But not completely. You can see this using a telescope *without* a lens, or any tube you find like a paper towel roll, to sharpen an image. Looking through a tube blocks many wayward photons that would blur the picture by coming from odd directions.)
The above describes bunches of photons behaving classically: in QM a single photon behaves similarly, since its wave function includes all of the paths it could be taking.

September 7, 2014

• ##### Mitch

I gues I have to vote on the "slightly frustrated" side when it comes to spending time watching videos together. (And I came late to avoid most of that.) If we pick videos early enough, can we safely assume most people will watch them at home?

1 · September 7, 2014

• ##### Michael

:)

September 7, 2014

• ##### Mitchell W.

Good tapes on General and Special Relativity.

September 7, 2014

• ##### Julian K.

Mitchell: Don't be despondent. Think how depressed Andrei Linde must have been for so many years when no one, including Alan Guth, paid any attention, especially early on, to the breakthrough ideas Linde had leading up to his profound vision of "Chaotic Inflation," "Eternal Inflation," and an "evolving multiverse." Worse than outright rejection, for many years Linde's profound insights faced complete and total neglect!

September 6, 2014

• ##### Vanessa

Hi everyone. Unfortunately I will not be a me to attend this meeting. Diana will be facilitating. See you next time!

September 6, 2014

• ##### Julian K.

Sorry. I just located the topic for our upcoming meeting on the Quantum Physics Discussion Group's "Welcome!/Recent Meetups" page." It's a bit confusing and inconvenient, because these pages are only indirectly linked to this page. Let me know if my Mac laptop is needed or helpful for this upcoming meeting as it has been in the recent past.

September 6, 2014

• ##### Mitchell W.

Depressed over poor book sales for my e book on kindle "TheEquation of Everything".Very difficult to sell a book to the general public.By the way time travel backwards may not be impossible.Besides a BigCrunch will may but hasn't been mathematically proven even by Steven Hawking drive times arrow backwards.It can be proven empirically if our acceleration and redshifts reverse and an atomic clock or cesium clock starts to slow down.Also if negative mass exists whether it be antimatter or not it must go backwards in time and can't move forward just as it seems be must move forward and can't go backwards.

September 6, 2014

• ##### A former member

Julian, I will provide all the equipment, so we will not need your Mac for this presentation.

September 6, 2014

• ##### Julian K.

That's a good question. Exactly what is our topic and/or program for this Sunday? Am I wrong in sensing a momentary leadership vacuum taking hold in our Quantum Physics discussion group? I certainly hope not, but if it is we should attempt to address the issue and start to rectify it at our upcoming meeting. What Vanessa set in motion has proven to many of us to be too valuable to lose.

September 4, 2014

• ##### Amrik S.

Do we have a topic for this meeting?

September 4, 2014

• ##### Mitchell W.

I got a lift for Sunday thanks for the offer.

September 3, 2014

• ##### Julian K.

Mitchell: I'm driving to the meeting on Sunday from my home in Santa Clarita. I don't mind in the slightest going out of my way to pick you up and then take you back after the meeting. Sincerely, I have the time and I'd be very happy to do it. Your contributions to the group discussions have been valuable. Please don't hesitate to contact me at[masked] or [masked].

September 2, 2014

• ##### Mitchell W.

Will try to come Sunday if I can succor transportationHave a stalling problem with my car that wasn't repaired .Cant guarantee attendance

September 2, 2014

• ##### A former member

I am not available for this meeting, looking forward to making the next event.

September 1, 2014

• ##### Ugo C.

Of all the QM Interpretations, some people like the Everett-Multi Worlds Interpretation (MWI) because it’s deterministic, gets rid of the concept of wave function collapse, and does not add new equations. But the problem is how to reconcile a deterministic interpretation of QM with the probabilistic Born rule (which is still used in MWI).
Sean Carroll, a Caltech cosmologist and MWI supporter, tries to provide that reconciling explanation in a recent paper at http://arxiv.org/abs/arXiv:1405.7577 (he also recently blogged on the subject, see http://www.preposterousuniverse.com/blog/2014/07/24/why-probability-in-quantum-mechanics-is-given-by-the-wave-function-squared ) . He uses the concept of probability at an epistemic level, not an operational level like in the Copenhagen interpretation. But his explanation feels a little bit ad-hoc and contrived to me. What do you guys think?

July 28, 2014

• ##### Ugo C.

Mitch, you are right, whether we talk about collapse or not we still need to define what happens at that point and why. That varies according to different interpretations. In the MWI, for instance, decoherece does it. In the Ghirardi-Rimini-Weber interpretation the function collapses spontaneously and randomly. Etc.

August 30, 2014

• ##### Ugo C.

It is interesting to notice how far we have moved away from some original interpretations where only conscious beings could affect the state of the wave function (which did not make any sense, at least to me). Unfortunately the underlying ontology (assuming there is one) of what is actually happening is still underdetermined by our current experimental capabilities. In other words, different interpretations yield identical experimental predictions, without a way to falsify a particular interpretation on an experimental basis. So the act of subscribing to a particular interpretation becomes a matter of subjective preference rather than a choice based on experimental results.

August 30, 2014

• ##### Katherine B.

I'm going to miss this meeting. I'm hoping you won't be meeting the first Sunday of every month since I'm rooted in Laguna Hills on those days. In case you need a shot of philosophy in my absence take a look at why physicists are hating on philosophy. Note the sentence: "Something strange happened on the way to the modern intersection of cosmology and foundational physics." How can I get this link on this page?
http://www.npr.org/blogs/13.7/2012/05/01/151752815/blackboard-rumble-why-are-physicists-hating-on-philosophy-and-philosophers

August 22, 2014

• ##### Ayman

August 6, 2014

• ##### Ugo C.

New QM paradox announced today: the Quantum Cheshire Cat, or how to separate neutrons from their spin: http://www.sciencedaily.com/releases/2014/07/140729123803.htm - pretty amazing stuff

July 29, 2014

• ##### A former member

I'm also willing to pitch with the group, for a plane ticket and board accommodations for another physicist to visit the group, Lene Vestergaard from Harvard University. I believe her work closes ties into Quantum computing. http://www.youtube.com/watch?v=EK6HxdUQm5s

https://www.physics.harvard.edu/people/facpages/hau

Anyone else?

July 28, 2014

• ##### A former member

John, For me it's not unrealistic, I've done things like this before and there are people who are willing to do those kinds of things, my suggestion was based off experience, not wishful thinking and the fact that I am not an organizer, I suggested. I also rather advertise my optimism then pessimism. That's what I teach my kids anyways. No worries, I'm just saying I'm willing to support this wonderful group that way. I am fine with a video too. I was very grateful Vanessa setup Dr. Sheldon Smith to come, and I am grateful she pays the meetup fee's too to keep the group going and doesn't charge a fee for us joining or listening to guest speakers.

July 28, 2014

• ##### A former member

Professor Lene Vestergaard Hau , doesn't have to fly down either, maybe she would be willing to skype with us, webinar, for our group or whatever it all depends on how Vanessa reaches out to her, and this was just a suggestion. I don't know about you, but I for one am a fan of Professor Hau and her work as well as Professor Andrew Cleland from U.C. Santa Barbara, I do not consider this group a "lay" or layman group of people of no importance for the subjects presented but see us as a group of people who are fans, admirers, thinkers, inventors, investors, or whatever and most importantly humble intellectuals that have fondness and love for the quantum and anything of/from it.

July 28, 2014

### 20 went

• ##### Mitchell W.
• A former member
• A former member
• A former member
• A former member
• A former member

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