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Monday, June 20, 2016

One for Clovis ...

... or maybe Hey Skipper's son and his BMW.

18 comments:

Clovis e Adri said...

Thanks, I know where they've bought it.

I used to be an APS member, before the dollar went up so fast it turned red :-)

Peter said...

“It’s about showing the fun side of physics,” Pirnat said. She added that some of the best selling items so far were the “Flirt Harder, I’m a Physicist” T-shirts and a red bumper sticker that reads “If this sticker is blue, then you are driving too fast.”

I see you physicists have the same screamingly hilarious sense of self-mockery as we lawyers.

Bret said...

LOL. Now I'm definitely glad I posted that.

Hey Skipper said...

Having been on the Autobahn, the reason that the sticker is red is because the other guy is driving too fast.

erp said...

Skipper, please explain using non-scientific terminology how a sticker (a piece of paper with glue on the back as I know it) can turn colors due to the actions of a vehicle to which it is not attached.

Aside: It's getting really scary that there are so many typos in my comments even after I've re-read them several times. I'm only explaining because it's not from inattention. :-(

Bret said...

erp asks: "...please explain using non-scientific terminology..."

Totally non-scientific? Tricky. But here goes nothing.

You know how when you drive towards a car whose driver is leaning on the horn the horn sounds higher in pitch as you're driving towards it but suddenly drops in pitch as you pass it and start driving away from it? [If we were allowed to use scientific terminology it's called the Doppler effect].

Well, colors do the same thing for the same reasons. However, instead of going some fraction of the speed of sound to notice the effect, you have to go some fraction of the speed of light. If you drive very fast towards the car the color of everything on the car including the sticker will shift towards the blue end of the spectrum (I'll leave it Clovis or Skipper to tell us exactly how fast one would have to be going to see that red sticker as blue). As you drive away very fast the color will shift towards the red end of the spectrum. Skipper is saying that the cars on the Autobahn are driving away from him so fast that their blue stickers looks red.

This effect is sorta visible in real life in that if you look at distant galaxies through a telescope, they look redder than they would if the effect didn't exist and indeed they kinda sorta look very slightly redder than stars within this galaxy if someone points it out and you use your imagination (or perhaps have a very good telescope).

erp said...

I'm a very fast driver myself (in my youth even raced my father's Pontiac with the boys on the beach), but even so, I've never noticed colors changing before my eyes. I'll try to be more observant. And your explanation was very clear even if I don't believe a word of it. :-)

Bret said...

I'll leave it to the physicists to double-check, but by my calculations, to see red as blue you have to go about 1/3 the speed of light. That's boogieing!!

erp said...

You said it boy!

And guys, don't explain. Physics gave me a headache when I had a head to ache and I'm only kidding (kinda) when I say it's nonsensical.

Hey Skipper said...

Bret, that seems right, since that is about as fast as the 911 Carrera Turbo was going by me.

erp said...
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Clovis e Adri said...

Erp,

Nice picture! I would whistle if my keyboard allowed...

Clovis e Adri said...

Erp,

Though Bret's has done a ve ry good job of it, you may also want to check this explanation by Carl Sagan himself, since you look to like the guy.

erp said...

Clovis, thanks for the compliment.

I neither like nor dislike Sagan. When "Cosmos I" was first aired Sagan was roundly ridiculed for his pomposity, but I don't remember the series being faulted for inaccuracies (I might be wrong here, but that's my memory).

... and I take what he and the rest of you scientists say as probably true because I have no evidence to the contrary, but I strongly suspect, we are in a big zoo and the firmament is merely out there to amuse and amaze us and keep us occupied.

I simply cannot wrap my mind around "without beginning or end."

Bret said...

erp was a hot chick once upon a time! I've never been into old cars, but the car is kinda cool too.

erp wrote: 'I simply cannot wrap my mind around "without beginning or end."'

That's funny, because I can't wrap my head around there being a beginning and can easily wrap my head around infinite in all dimensions.

erp said...
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erp said...
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erp said...

Don't know why the Dropbox pictures I posted have other pictures tagged on. Anyway, they weren't supposed to be there. If the way my relatively simple devices work is similar to our defense department, etc., it's really, really scary.