emcelhannon

Thanks Toasty,

I completely reversed the question on mass. Thanks for the correction and explanation. On technium however, I understand that it has no stable isotope, but I don't understand why. It's easy to accept the instability of heavy atoms, though I don't fully understand why. I would assume it involves a weight to energy ratio?

I might as well ask why 83 and up are unstable, but I'm especially currious about what makes 43 so different from the 20 before and after.

Why is technitium radioactive?

Why is the atomic mass of potassium greater than argon, nickle greater than cobalt?

In buying clock/watch hands, how can I tell promethium from radium?

it's going to be in that state until it interacts again.

When it interacts again, does it enter a different eigenstate, or does it convert to a wave?

I read everything I could read in 2 hours on eigenstates, but I'd appreciate a customized definition here.

Thanks

Merged post follows:

5:21 am?! Holy cow, Swansont. Don't you sleep?

"detection is typically destructive for a photon, but not so for interactions that collapse the wave function."

I'm afraid I don't follow. If you wouldn't mind, dumb it down a little. I'm trying to distinguish between a particle’s natural interactions and those with a detector.

I confess, I skimmed most of this thread to see if my question has already been answered.

After the particle has been measured, does it keep the spin detected or go right back to having "no spin?"

Is the particle not interacting with other particles and "wave colapsers" before and after the detection?

Is the detection very different than every other interaction with a photons throughout?

This really is interesting. It's less complicated than the infinities involved in a singularity. I would like to understand more about why the string grows, and how. Fill me in, and what limit would likely equal "critical mass"?

The experimental upper limit on the photon mass is very small and consistent with zero.

Thank you,

What about volume?

Can the photon's electric field rotate or tumble, (as in N up S up N) or is it's orientation fixed between interactions? Being massless, it's hard to imagine angular momentum. Is it proven that the photon is massless?

You're the man, Swansont,and I think I'm keeping up. Is polarization related to spin, or are they separate properties?

Pardon me if this question belongs in a different thread.

If i put out several posts in different threads, can I recieve some notification that there has been a reply in one of those threads? Checking every thread individually is time consuming.

Also, I've noticed that when I view someone elses personal page, it shows the names of the most recent visitors. When I check my own page, it tells me the number of visitors, and a white box with a red x in the upper right of that cell. No names are listed.

Entanglement means that all of the information you are getting is encoded in both photons. So measuring one tells you about both. Saying that the measurement has an "instantaneous effect on the other" isn't an accurate reflection of the phenomenon.

How is this concept not consistant with a local hidden varriable theory. What did the Aspect experiment prove, if it's not the non-locality of quantum effect, or it's hidden varriables?

(I don't know how to insert two quotes in one message)

(second quote from Swansont)

"The difficulty in the analogy, as I stated before, is that the ball doesn't have a color initially, and doesn't have one until you measure it. So the obvious question is, "How does the other ball find out what color the first ball is?" It's not a dumb question, and understanding the answer requires QM. It's not a classical phenomenon, so classical analogies will always be of limited usefulness. "

So, without analogy, how can the information already be encoded in both particles, and yet not have any state whatsoever except that it's entangled?

So is it possible to entangle 3 or more particles?

How many quantities or even combinations can particles be entangled? If they are few, what are they?

Is evey particle entangled in some way with the last particle it enteracted with?

Does it automatically loose all entanglement with its previous partner upon impact?

Is polarization the wave counterpart to the particle spin?

Got it. You hit on just what I was missing.

Thanks again

Thanks for trying, but I'm feeling a little obtuse. Just tell me to kiss off when you start to feel like your talking to a wall.

It might help if I pull specific information from the article that confuses me. In our previous posts we discussed that measured light that has been collapsed and light that remains in a superposition are indistinguishable, because when it enters our measuring apparatus it always appears collapsed, (because we just measured it)

(This is where my misconception probably is. The slightly different language is intended to reveal possible errors in my understanding.)

The article reads, "By performing statistical tests on the light received at the other end of the cable, one can tell whether it remains in the superposition of states or has already been observed..." I'm assuming that "already been observed" means collapsed, and I should mention that I have no clue what statistical tests would be performed.

I'm also confounded by the final comment, " Such a test would only work if the collapse occurs after (as opposed to before) observation;"

I'm under the impression that observation equals collapse.

Gribbon published some theory about unbreakable codes using entanglement for communication in an afterword of one of his cat/kittens books. I thought I'd kept up with everything until that point. I couldn't make sense out of it, so I feel I missed something fundamental somewhere. It's been years since I read that book. Even after reading many books, and periodicals in the field, my comprehension of the standard model seems coherent....except for this shortcoming.

I'm beginning to think my neurons just aren't packed tight enough to make the connection.

I appreciate your patience, even if you're only able to be patient till now.

Alright Swansont,

I've done some reading, per the advice of some moderators, on Wikipedia. What I read here seems contradictory, but I suspect that I'm assuming something that should not be assumed.

In the Schrodinger's Cat article, under Practical applications it reads, "It is possible to send light that is in a superposition of states down a fiber optic cable. Placing a wiretap in the middle of the cable that intercepts and retransmits the transmission will collapse the wave function (in the Copenhagen interpretation, "perform an observation") and cause the light to fall into one state or another. By performing statistical tests on the light received at the other end of the cable, one can tell whether it remains in the superposition of states or has already been observed and retransmitted. In principle, this allows the development of communication systems that cannot be tapped without the tap being noticed at the other end.... This experiment can be argued to illustrate that "observation" in the Copenhagen interpretation has nothing to do with consciousness (unless some version of panpsychism is true), in that a perfectly unconscious wiretap will cause the statistics at the end of the wire to be different. Such a test would only work if the collapse occurs after (as opposed to before) observation; otherwise, it would appear collapsed whether it had been wiretapped or not."

Is this article stating that we can tell if a collapse has or has not occurred prior to our measurement?

But be warned — there is a lot of chaff and little wheat, i.e. there is often little physics in he discussion.

Perhaps you could reccomend a reputalbe author.

thanks

Thank you J.C.,

It was an interesting book, but I meant the "well beyond the scope of the original thought experiment" part.

I thought I understood it as far as I was capable, so I expected a cat initiated test, (although I didn't know why) would likely have the same results as every other similar thought experiment. If there's more to be considered along these lines, I'm terribly interested, but I don't want to change the subject of this thread.

That's a topic of discussion by some, but it goes well beyond the scope of the original thought experiment.

Well, that's tantalizing. Who would I read if I wanted see some theories on the subject?

Thanks

In the single cat thought experiment would it make a difference if the measurement were initiated by the cat?

Surly I've met many crows who are a site smarter than some people, but I'm not really interested in human intelligence at the moment.

I would be more interested in learning how it's different than a rodent pushing on a lever for food. What do you think is a likely range of reasoning for the crow with the stones, or the bent wire, or the vending machine?

because much of trial and error learning (and execution of experiment) requires some remedial level basic idea of a system and how it works, as well as a desired outcome motivating the action. .

Thank you for your response.

I have to dissagree.

Behavior motivated by one situation can lead to solutions of otherwise unrelated problems. The fact that they are intelligent enough to remember, learn (even from each other) and repeat is amazing. They see that throwing in stones brings the food closer.

I think it's clearly established that they remember and learn. Can they think?

The first crow to try this: did he think, "If I throw this stone in there, it should raise the water level, and maybe I can reach the worm."? What clues can you glean from the experiment to help you divine the intentions of that first productive act. If you can establish that these crows anticipated the result before the first attempt, that would be truly awesome.

Intelligence isn't quantified by what you can do. In Kentucky the cliche goes, "Even a blind pig can find an acorn, once in a while."

"Birds seem to demonstrate both of those things"

I suspect that they do, but, do you know some specific examples, offhand?

Could you not ask the same question regarding the approach humans take? I really don't see any difference here between us in them... at least... not in that respect.

That wasn't exactly my question. I've meet many people, I'm fairly certain are less intellegent than crows. I've beaten the radio a few times and gotten it to work. Now it's my first response to a lot of malfunctioning tech. But I'm also capable of analyzing how a system must work, and developing an experiment to test my thoughts.

What I want to know is do they develop an idea, (a hypothosis) before they "experiment?"

Do we feel it's gravity? Is it what dark matter theories are made to explain?

I guess my next question is: from this information, can we conclude that they hypothosize before they experiment, or do they merely remember the results of "happy accedents?" "Hey this sucks. Let's throw stuff at it. Look it worked!"

I would like to believe there is more to it than that, but the birds with the vending machine were trained through a 4 step process.

That's an interesting distinction, jimmy. How would the crows be able to consistantly exhibit that behavior without understanding?

I would imagine that random trial and error could eventually solve some of their problems, without them understanding why. I would be interested in seeing some of their failed attempts before their successes. That's where the answer to your question is. Obviously, they have a good memory, but are their efforts random or are their attempts focused on rational ideas?