Awesome Physics Teacher Dan Burns Explains Gravity In A Way Anyone Can Understand
General relativity, the geometric theory of gravity developed by Albert Einstein in the early 1900’s, is today considered one of the twin pillars of modern physics. Along with quantum mechanics, it is fundamental to our understanding of the universe.
Yet despite its importance, general relativity doesn’t always get the classroom attention it deserves.
"Is general relativity in the state standards? No. Probably the crowning achievement of science not in the state standards," Dan Burns, a physics teacher at Los Gatos High School in California, says in the video above. But that didn’t stop Burns from coming up with an ingenious demonstration to help students understand concepts that are notoriously tricky.
As Burns explains in the video, which was posted by apbiolghs on YouTube, matter bends space. He demonstrates that idea with the help of a stretched sheet of lycra, a pair of weights, and a few marbles. When set in motion on the lycra, the smaller marbles circle the much heavier weights, coming closer with each turn until they connect.
The video helps students wrap their minds around a number of complicated concepts. Class is in session!
There’s a winged liner “terminology” reference list going around and I decided to give them correct names.
every Doctor Who theme at once
This is how i felt when all the doctors joined together to save Gallifrey.
this would suit Capaldi perfectly
the opening sequence can just be this gif
I love a little too much how everyone’s predictions for Capaldi’s Doctor is that his personality is just gonna be raw uncontainable fury 100% of the time
Saturday by Rebecca Black (feat. Dave Days)
and just like that, the queen has returned and dethroned all of our faves with one swift motion
SHE CAME BACK WITH THE FLAMES
Who’s ready for Sunday?
Coconut & Rice-Coated Banana Fritters With Coconut Cream
it felt like i knew you…, 2012 - ongoingI ride the NYC subway trains, usually in the evening when the seats are full. I focus on the shape of the space between the person sitting next to me and myself. I attempt to mentally and emotionally re-sculpt that space. In my mind, I reshape it- from the stiff and guarded space between strangers to the soft and yielding space between friends. I direct all my energy to this space between us. When the space palpably changes, and I completely feel like the stranger sitting next to me is my friend, I rest my head on that person’s shoulder…
i’d like to temper this by saying that i’m not a medical professional, or even the best person in my immediate peergroup to address this (nerds feel free to jump in here).
it would be “cool” if people were only able to doom themselves with their awful decisions, but in circumstances like this it doesn’t work like that. you’re right, yes, that vaccinating one’s child is a choice insofar as nobody is going to force you to get vaccinated. it’s a choice in the same way that any other objectively beneficial medical option is a choice— you’re allowed to not make that call, but nobody is going to congratulate you for doing so.
one of the issues here is that not getting vaccinated doesn’t just harm the unvaccinated person. not only do vaccines not have a 100% success rate, there are also plenty of people with completely legitimate medical reasons (like yourself) to not get vaccinated. ain’t nobody gonna get on your case for having a deadly allergy. maybe someone missed their booster shot or whatever. maybe you don’t have access to proper medical care, or can’t afford it. you’re probably gonna be safe, because:
luckily, because so many other people have gotten vaccinated around you, you’re protected by what’s called herd immunity. this is a really cool phenomenon, by which a large ratio of protected individuals are able to provide a larger protection to an entire community— effectively stopping the spread of a given disease by way of cutting off infection vectors. you’re insulated from the spread of a disease by a cushion of vaccinated people, none of whom can transmit the disease to you. you are effectively immune (even though you aren’t vaccinated), because the disease has no way of getting to you.
this starts to break down when higher and higher ratios of people are no longer vaccinated. the disease is able to spread across a group with greater ease, simply by virtue of having more infection options. this is why we see large outbreaks of eradicated diseases like in brooklyn or texas; because a statistically higher ratio of people in a given community are unvaccinated, the infection is able to spread farther than it ever should have been able to. i found this cool youtube which breaks down the “blocking” concept a little better than i might be explaining it:
another issue here is that the “choice” antivax parents are making is objectively, factually incorrect. vaccines work, they don’t cause autism or contain tons of dangerous chemicals, and they’re usually not a vehicle for the CIA to steal our DNA. we know because we have decades of rigorous scientific evidence backing us up— we are “scientifically correct” about vaccines, which is not a status that is given lightly. you gotta earn scientific correctness, over many years. as more parents start to think that it’s okay to not get their kids vaccinated, they start to undermine a very delicate system with potentially devastating consequences. (google translate from dutch, but the gist of it is that the netherlands is in the middle of a 2500+ person measles outbreak this year, largely spurred by a larger ratio of antivax/alternative care in a community. herd immunity, ya’ll.)
not getting your child vaccinated because a medical issue will cause them more harm than the vaccine itself would prevent is completely reasonable and acceptable. not getting your child vaccinated because you think medical science is a fake idea is not.
i am also not a medical professional so someone can correct me here but if i remember correctly, vaccination is also incredibly important to protect infants from deadly diseases they cannot get vaccinated for but CAN contract from someone who has not been vaccinated. Measles for instance will kill a baby stone dead, but you can’t vaccinate them for it until they’re older than 12 months. so the health and survival of infants vs. measles is directly dependant upon the vaccination status of the infant’s surroundings.
It is also spread through respiration (breathing on someone) and has a 90% transmission rate within regular contacted individuals, AND has a 12 day incubation period where you have no idea you contracted the disease but are still spreading it around. this is zombie outbreak level pandemic horror, and it used to kill people (mostly children) in the United States by the hundreds of thousands within living memory. measles fatality was nearly 800,000/year in the US circa 1960. fatality rate is 30% in an infected group!!!
and that’s just measles. thats not even polio or any of the other things we vaccinate for.
I can vouch for what ghostbong said. I’m not a medical doctor, so you can’t construe what I’m saying as specific medical advice for your case., but I am a virologist, so you can construe what I’m saying as informed scientific fact.
I can’t quite support what Eliza has said here, it’s…a bit off, so I hope you don’t mind the correction. The current vaccination schedule recommends given the Measles/Mumps/Rubella combined vaccination beginning at 6-12 months, mostly because before 6 months in most kids, vaccines are fairly ineffective. We’re still relying on maternal antibodies at that point; we get these in our blood from our mothers and from milk, to some degree.
So while it’s important to keep your children away from unvaccinated persons, it’s even more important to be certain that the mother is vaccinated against these diseases.
In fact, rubella is not much more harmful than the flu—the scariest danger in rubella is that if your mother has it while she’s pregnant with you, you’ll come out with birth defects. Pretty scary! So it’s super important that would-be moms get up to date, if they don’t want to put their kids at risk.
I think Eliza’s being a bit alarmist about the severity of measles virus infection, though. It is survivable with modern medicine, and after a lengthy hospital stay, an infected baby will probably be able to return to lead a normal life with minimal complications. I say that hoping readers catch my full irony. Vaccinated babies don’t have those risks.
More importantly, in a small percentage of patients who have measles as children, you get a violent, 2-week encephalitis called SSPE around age 30 and ultimately die. It’s sudden, it’s caused by reemergence of a latent measles infection, and it’s a painful, brutal way to day. Your brain swells, you lose your mind, and then you die. Not sure if it’s 100% fatal, but it’s 100% awful. Now that’s zombie-apocalypse type stuff right there.
She is, however, correct that measles spreads like wildfire. It’s an unbelievable virus in how it transmits, and the statistics Eliza cited are correct, but they blunt the nutso-cracked-out-transmission of MeV.
In epidemiology they have this concept called “r-naught,” which is basically the coefficient of the number of people one infected person will infect. In the movie Contagion it’s talked about in detail—great movie, check it out.
For flu, this spread coefficient is 1. One infected person makes an average of one other person sick. Remember how the 2009 flu pandemic went global in a month? That’s what an r-naught of one looks like.
Measles virus has an r-naught of fifteen. If you’re unvaccinated, you can catch measles just from being within 100 feet of someone who has the virus. You might never even touch them.
This is some scary stuff, ladies and gentlemen.
important update from an irl virologist. sorry about the bad facts john, i was working from wikipedia instead of actual current research etc