Recent content by Phinrich

Dear Sysprog. Thanks a million. Much appreciated. Paul

Summary:: Searching for Paper by R H Dicke Good day all. Does anyone know where I might obtain a copy of the Paper R. H. Dicke. Gravitation without a principle of equivalence. Review of Modern Physics, 29(3):363–376, 1957 I am prepared to pay for it. Thanks Paul

Hi I have not yet read any of the previous replies so what I am saying here may have already been covered. If we interpret the Equivalence Principle to say that, an observer in a freely falling reference frame (elevator) will not be able to tell if he is in free fall in a gravitational field...

TRUE! That's a GOOD one. I'd rather take my chances with a little radiation than with a little extinction THANK YOU! At least until Mr. Musk gets us colonizing Mars.

Thank you for your comment. You are ABSOLUTELY correct. We are exposed to little bits of radiation every day and the species has been exposed for millennia and it is certainly possible that a little radiation is good for us and may in fact help with the evolution of the species. I didn't want to...

The following link may be of interest to you...

It's a pleasure. It is 22:30 here and I am retiring for the night. If you ask more questions I will answer them tomorrow. Have a GREAT day.

I am afraid I have very little experience with Americium smoke detectors. Although I work for my countries nuclear regulator the regulation of smoke detectors is handled by another regulator. I have spoken to you about the principles and practice of radiation protection, in general. My point was...

Hope the answers were not too detailed. I was trying to put your mind at ease. I agree with the Physicist regarding where the yellow dust could have come from and also I agree that it is "dangerous" in the sense that, although the quantity of radioactivity is small, it's a good policy to keep...

Speaking of having radioactive material inside your eye, in an earlier job I worked as a medical physicist at a large hospital with a radiotherapy Unit. There is a rare condition known as Retinoblastoma which leads to a cancer tumour inside the patient's eyeball. We would treat this condition...

Off the top of my head, I would answer as follows. Firstly, I am not encouraging you to eat the Americium 241 source, but when I say that the exemption of the source (based on a level of 5 mico-curies activity), is based upon assessing all possible ways for you to be exposed to it, that would...

Having said that, it's good practice to keep away from radiation if you can avoid it. That's easier said than done as radioactivity is a natural phenomenon and we are all surrounded by it every day without even being aware.

Good day. As a Radiation Protection Specialist, with 30 years of experience, I can assure you that the risk to you, from fiddling with the Americium-241 source inside your smoke detector, is negligible. The quantity of radioactivty in such a detector is, in regulatory jargon, Exempt from being...

Good day, all. Further to this old discussion (in case anyone is interested), If you Google "Dual Basis" you will find a Wikipedia Article which says the following; In Linear Algebra, given a vector space, V with a basis B of vectors indexed by an index set I, the dual set of B is a set B∗ of...

Hi Thanks for your I believe that you are right. In trying to understand this I watched a few videos on Youtube and in one the Lecturer was trying to explain what "isomorphism" was and he said something like what you have said. I don't remember all the finer mathematical points but he showed...