Commenter miller asks: It’s often said that virtual particles can “borrow” energy, as long as it’s for a short enough time to be compatible with the uncertainty principle. This never made sense to me, because the uncertainty principle says that product of uncertainty in energy and uncertainty in time is greater than h-bar over 2,… Continue reading Reader Request: Borrowing Energy
Category: Physics
Reader Request: Quantum Complexity
There’s some good stuff in yesterday’s post asking what physics you’d like to read more about. I’m nursing a sore neck and shoulder, so I’ll only do one or two quick ones today, starting with James D. Miller in the first comment: 1) Is it true that our understanding of quantum physics comes from studying… Continue reading Reader Request: Quantum Complexity
Should Doctors Have to Take Physics and Chemistry?
The New York Times today has a story with the provocative title Getting Into Med School Without Hard Sciences, about a program at Mount Sinai that allows students to go to med school without taking the three things most dreaded by pre-meds: physics, organic chemistry, and the MCAT: [I]t came as a total shock to… Continue reading Should Doctors Have to Take Physics and Chemistry?
Two Cultures Defining Research
I was initially puzzled by the headline “Research-Assignment Handouts Give Students Meager Guidance, Survey Finds,” and the opening sentences didn’t help much: Most research-assignment handouts given to undergraduates fail to guide the students toward a comprehensive strategy for completing the work, according to two researchers at the University of Washington who are studying how students… Continue reading Two Cultures Defining Research
What Physics Topics Would You Like to Read About?
I had intended to write up a recent paper for ResearchBlogging today, but I cleverly forgot to bring either the hard copy of the PDF home last night, which wrecked that plan. And I’ve got real lab work to do today, so it’s not happening at work. This seems like a good opportunity, though, to… Continue reading What Physics Topics Would You Like to Read About?
Dorky Poll: Experimental Hazing
I’m going to be spending a good chunk of the rest of my day scrounging up adapters to connect two different classes of plumbing fittings. In honor of that, here’s a poll question based on something that one research group used to do: Sending a new graduate student to the lab down the hall to… Continue reading Dorky Poll: Experimental Hazing
When Should You Open Your Car Windows? An Experiment
Back at the start of the summer, I asked a question about automotive thermodynamics: On a hot day, is it better to open your car windows a crack when making a short stop, or leave them closed? For a long term– say, leaving your car parked outside all day– I hope everyone will agree that… Continue reading When Should You Open Your Car Windows? An Experiment
String Theory in Complete Sentences
On Twitter, I saw Graham Farmelo link to this Physics World blog post about Ed Witten’s Newton lecture, describing it as “Edward Witten’s clearest-ever overview of string theory for laypeople (i.e. most others).” Witten’s a name to conjure with, so I thought “That might be worth a look.” So I went to the blog post,… Continue reading String Theory in Complete Sentences
Measuring Temperature by Counting Atoms: “Suppressed Fluctuations in Fermi Gases”
When one of the most recent issues of Physical Review Letters hit my inbox, I immediately flagged these two papers as something to write up for ResearchBlogging. This I looked at the accompanying viewpoint in Physics, and discovered that Chris Westbrook already did most of the work for me. And, as a bonus, you can… Continue reading Measuring Temperature by Counting Atoms: “Suppressed Fluctuations in Fermi Gases”
Electron Spin for Toddlers
The subject of the “spin” of the electron comes up again and again, so as pointed out in a comment, I really ought to do a post explaining what it is and how it works. As a bonus, this gives me the opportunity to do the dorkiest thing anyone has ever done with a cute-toddler… Continue reading Electron Spin for Toddlers