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Why We Think There's a Multiverse, Not Just Our Universe

JoeRobe Re:My God... (458 comments)

I agree with all your points here. It seems like the "standard picture of inflation" curve is the crux of everything, and is referred to repeatedly. But he doesn't even define the axes well. (I agree with your complaint about the axes - he says the y-axis is energy, but the x-axis is specifically in units of energy).

I'm unclear on one apparently critical point that maybe someone can clarify. I see what he's saying that the universe dominated by vacuum energy expands much more quickly than one dominated by radiation or matter. But does this mean that it's expanding faster the the speed of light? It seems to me that he's saying the multiverse happens because there are these pockets within the multiverse of slow expansion (an individual universe within the "well") and fast expansion in between, right? But then the only way those pockets could not be observable between each other is if the "fast expansion" region is faster than light. Why does the fact the the expansion doesn't slow down in a vacuum dominated universe mean that certain parts of the universe are out of reach of other parts. Is gravity the culprit here?

Part of this comes down to his equation(s):

size ~ t^n, where n = 2/3, 1/2, or 1

First of all, what is "size"? Volume? Length? Area?

Second, and most importantly, why isn't that expansion rate linear in time for everything. What is it about the physics that makes a matter dominated universe expand differently than a radiation-dominated universe? Is that easy to explain? And if so, that's crucial for my understanding here.

Something that's never been clear to me in the expanding universe model is why the expansion of the universe results in red-shifting of light and shifting of the CMB to the microwave region. Can someone explain this? If the expansion is of space itself, which I interpret as the "grid" upon which matter/radiation exists, how does light or anything else know that the grid is expanding? In the silly picture in my head, I'm thinking that I won't know that my ruler is changing length since I'm changing length with it, just like how person A moving at near the speed of light relative to person B doesn't know that the space that they're in has "shrunk" according to person B. In the model of the expanding balloon with ants on the surface, how do the ants know that the expansion is occurring? If I were one of the ants, I'd draw a grid around me out to the next nearest ant. As the balloon (universe) expands, the grid would expand with it, so I would have no idea that the next ant is getting further away. Why is it different in the universe expanding? Is it just radiation that knows of the expansion? I'm clearly missing an important concept, but I don't know what it is.

about 8 months ago
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Finnish HIV Vaccine Testing To Begin

JoeRobe Re:Is it a "Vaccine" or a "Cure" (72 comments)

Not sure why this is a troll, but I wish I had mod points to bump it up. I'm not the OP, but I was wondering the same thing regarding how this was a vaccine. This explanation makes complete sense and thanks for the clarification.

Just so I'm understanding correctly: the amount of HIV virus in the blood is very small after initial infection, so the idea is to use the vaccine to keep the level low (i.e. prevent the virus from ever ramping up again and destroying your immune system)?

So this would prevent infection for those without HIV, and keep HIV dormant for those that already are infected?

about 9 months ago
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George Zimmerman Acquitted In Death of Trayvon Martin

JoeRobe Re: not surprised at racism and naive WASPs (1737 comments)

To follow up on that: jurors are not selected randomly. The defense and prosecution pick from a larger set of jurors. What are the chances all jurors would be female? That is 1.6% but not a coincidence. The prosecution surely would have gotten a couple of black people on the jury if they thought they had a solid race argument. Rather they opted for the female/mother angle ("what if Trayvon was your child?").

A lot of folks are asking what would have happened if Martin was white and Zimmerman was black. I think it's a good question to ask, and unfortunately the verdict could have been very different. Another question that I'd like those people to ask is "what if Zimmerman's last name was Sanchez, or Juarez, or Mesa (his mom's maiden name)?". Would there still be these claims of racism?

about a year ago
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Opportunity Breaks NASA's 40-Year Roving Record

JoeRobe Re:Soviet Strong (92 comments)

Where does 7 to 1 come from? 7 to 1 of what?

I think NASA's done pretty well for itself...

about a year ago
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NASA's Ion Thruster Sets Continuous Operation Record

JoeRobe Re: Um, they used what? (165 comments)

I'm a mass spec guy, so I certainly agree that different masses will focus differently. But in the ion drive schematics I see online, I don't see where there is a focussing step. The plasma is made, then just accelerated across a planar electrostatic voltage drop. No focussing needed. I'm also not seeing a x2 increase just from a slightly better ability to focus even if that did matter.

about a year and a half ago
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NASA's Ion Thruster Sets Continuous Operation Record

JoeRobe Re: Um, they used what? (165 comments)

Why would isotopic purification increase the efficiency by a factor of 2?

about a year and a half ago
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Who Should Manage the Nuclear Weapons Complex, Civilians Or Military?

JoeRobe Re:Computers (183 comments)

I prefer WOPR.

Or maybe Joshua...

about a year ago
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Schmidt On Why Tax Avoidance is Good, Robot Workers, and Google Fiber

JoeRobe Re:Question (780 comments)

I agree that they should be paying taxes on money earned in the UK. But I would argue that the responsibility falls upon the government to create laws that fill in the loopholes and reduce deductions, rather than the company to apply its arbitrary set of ethical standards, in determining how much money the company owes to the government.

To rely on the company to decide how much to pay is equivalent to asking it to donate money to the government, which the company (or anybody for that matter) are not obliged to do.

about 2 years ago
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Schmidt On Why Tax Avoidance is Good, Robot Workers, and Google Fiber

JoeRobe Re:Question (780 comments)

Isn't the point of having a tax code so that we don't have to decide how much to pay in taxes based upon our ethics? The government tells us how much to pay based upon its tax code, so we pay it. At no point do they ask us to pay based upon our ethical standards.

I guess I wonder what should Google do. Should they pay the maximum amount the UK government wants, and avoid all possible deductions and loopholes? Or should they pick the "normal" deductions that other UK businesses use? Something in between? Which deductions/loopholes should they choose? Which ones are ethical? And by whose standards are they ethical?

I use my ethical standards when I donate to something like the Red Cross or UNICEF. I don't donate my money to the government. Taxes are a bill I pay to receive the benefits that the government provides to me. I'll find any way I can, within the letter of the law, to reduce that bill.

about 2 years ago
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Other Solar Systems Could Be More Habitable Than Ours

JoeRobe Re: So, maybe like Venus? (143 comments)

Do you happen to have a reference for your theory? The theories I've heard (which are proclaimed pessimistic) say nothing about water splitting due to solar radiation, but rather just evaporating and making its way up to the stratosphere, where it has a higher probability of being lost to space. It also sounds like the time frame for this process is not pinned down.

about 2 years ago
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Spectacular New Views of Saturn's Polar Vortex

JoeRobe Re:Pacman Returns (49 comments)

Welcome to the world of scientific research. It's a scientific article, which are almost always behind a paywall. ScienceDirect (operated by publisher Elsevier) is one of the largest scientific journal conglomerates. Universities pay 10's of thousands of dollars every year, if not more, to give their researchers access to these journals. So the authors make no money on it, but Elsevier makes loads on these articles.

about 2 years ago
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On Nov. 22, 2012, I expect to be ...

JoeRobe Re: 5+6 (340 comments)

No no I prefer the artificial cranberry jelly. That stuff is like crack to me.

about 2 years ago
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Amazon.com: Earth's Biggest Wine Cellar?

JoeRobe Re:Not in Alabama (118 comments)

Yeah I vaguely remember when I was a kid going to Ocean City in the summers and hearing my dad complain about OC being a dry town. He always had to run to the next town over to go pick up beer.

about 2 years ago
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Amazon.com: Earth's Biggest Wine Cellar?

JoeRobe Re:Not in Alabama (118 comments)

I'm originally from PA, and I couldn't agree with you more. I'm proud of a lot of things about PA (like Yuengling), but it has some really antiquated laws. I went to college in Pittsburgh, and every time we had a party on Saturday night, at 11:45p we would run out to the beer distributor and get another half-barrel, because once the clock struck 12, they couldn't sell any more.

I currently live in CT, and when I moved here I was completely floored by the fact that the supermarket had a whole aisle for beer! Quite a contrast to PA where you get carded just for walking into a liquor store.

Many more states in the country don't allow beer to be sold on Sundays. In some states (including PA), every once in awhile a politician floats the idea that they should start selling on Sundays, and supposedly local liquor/beer stores don't like it, because it means they'd have to pay staff to stay open one more day per week.

The Johnstown Flood Tax is such a joke, especially considering that, after a half dozen floods to hit the town (1936 was just one of them), Johnstown has been steadily shedding population (it's currently at a third of what it was during the 1930's).

about 2 years ago
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My relationship to military service:

JoeRobe Re:Missing option (525 comments)

Therefore No crime of war perpetrated by the US military can ever be trialed by an independant court

Actually the US can always re-sign and ratify the Rome statute, after which it will be possible to be tried for war crimes. As I understand it, they have problems with suspicion that American citizens who are brought to trial at the Hague may not receive due process, including a jury trial.

The US signed the Rome Statute at first under Clinton (but didn't ratify it), then the Bush administration revoked the signature (which would mean they really don't have to even pretend to abide by it). Now the current administration is showing signs of being interested in the ICC again, but they haven't directly stated that they want to sign or ratify it. It seems like a thin line the current administration is walking - they want other countries to be held accountable at the Hague, but not themselves quite yet. Maybe once the government isn't at war, they'll be more likely to ratify it (since war crimes prior to ratification can't be prosecuted).

I disagree with the statement that the US has perpetrated more crimes of war and crimes against humanity than any other nation. Although the US is by no means a saint, Sudan, Rwanda, Egypt, Syria, Cambodia, Iraq, North Korea, China, and others have had their share of crimes against humanity in the past 70 years, including genocide in some cases, without trial in an international court. Iraq 1 and 2, Kosovo, Vietnam, etc. aren't by their nature war crimes. War crimes do happen in every war, and I personally think people who commit them should be held accountable by the Hague (including Americans). But to say that the US as a whole has committed more crimes against humanity than, say Rwanda where 800,000 people were killed in 1994, or the Kmer Rouge which killed 1.7 million Cambodians in the late 1970's, is nonsense.

about 2 years ago
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Scientists Who Failed to Warn of Quake Found Guilty of Manslaughter

JoeRobe Re:Misleading summary (459 comments)

In addition to the absurdity of the case at all, there are a couple other things that bother me a lot about this:

1) the prosecution asked for 4 year sentences. The judge upped it to 6 years. How often does a judge go beyond the prosecution's requested sentence?

2) this was held in the town that got devastated by the quake. What are the chances that they'd get a fair trial?

Somehow they've successfully alienated the scientific community and made their own judicial system look like a joke at the same time. If I was a scientist on any government advisory committee in Italy, I'd be stepping down right about now.

about 2 years ago
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Where Has All the Xenon Gone?

JoeRobe Re:Another terrible summary (225 comments)

the second heaviest of the noble gasses

For what it's worth, actually it's "gases". "Gasses" is a present tense verb.

about 2 years ago
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Curiosity Spies Unidentified, Metallic Object On Mars

JoeRobe Re:If its is alien origin (396 comments)

it would overtun and eviserate that last remaining shred that mainstream religion(mormons ans scientology don't count)

Not Necessarily.

about 2 years ago
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Apple Acknowledges iPhone 5 Camera Flaw

JoeRobe Re:Stupid human! (472 comments)

Along those lines, it should be pointed out that in the laser (spectroscopy) community, if we want a window that's transparent in the UV and visible, we typically use sapphire. Glass (ie BK7, float glass, or the like) absorbs UV, and the alternative, quartz, is not as strong. So it would make sense if they wanted to switch to sapphire for its strength, but didn't consider its UV transparency. Has anyone opened the camera up to see what else is between the sapphire and the element?

about 2 years ago

Submissions

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16th-Century Map May Provide New Clues About The Fate Of The Roanoke Colony

JoeRobe JoeRobe writes  |  more than 2 years ago

JoeRobe (207552) writes "Roanoke Colony (on the coast of North Carolina) disappeared sometime between 1587 and 1590, with the only clue to its fate being the word "Croatoan" carved into a wooden post. Now, as if straight out of an Indiana Jones script, new clues to the whereabouts of the lost colony may have been discovered on a 16th-century map. The British Museum has re-examined the watercolor map to find a hidden symbol under a patch, in the shape of a 4-pointed star. The star likely indicates the location of an existing or intended fort that the settlers may have retreated to after abandoning the colony. Adding to the mystery, the patch overlaying the star may have been added in order to hide it from the "spy-riddled English court.""
Link to Original Source
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Large Solar Flare To Glance Off Earth

JoeRobe JoeRobe writes  |  more than 2 years ago

JoeRobe (207552) writes "According to spaceweather.com, a major X5 solar flare is on it's way to deliver a glancing blow to the Earth's magnetic field. This is the second x-class flare to be released by the same sunspot in the past few days, the first being an X1. In both cases, the sunspot (spot 1429) was not directly facing Earth, but it is still active, and poses a threat for a large, Earth-directed flare in the next few days."
Link to Original Source
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US Approves Two New Nuclear Reactors

JoeRobe JoeRobe writes  |  more than 2 years ago

JoeRobe (207552) writes "For the first time in 30 years, the US Nuclear Regulatory Commission has approved licenses to build two new nuclear reactors in Georgia. These are the first licenses to be issued since the Three Mile Island incident in 1979. The pair of facilities will cost $14 billion and produce 2.2 GW of power (able to power ~1 million homes). They will be Westinghouse AP1000 designs, which are the newest reactors approved by the NRC. These models passively cool their fuel rods using condensation and gravity, rather than electricity, preventing the possibility of another Fukushima Daiichi-type meltdown due to loss of power to cooling water pumps."
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New "Rubber Robot" able to crawl through small spa

JoeRobe JoeRobe writes  |  more than 2 years ago

JoeRobe (207552) writes "Researchers at Harvard have developed a pneumatically-controlled rubber robot that combines undulation and quadrupedal "crawling", allowing it to maintain a low profile while moving. In a paper in published in PNAS, they describe it as "A soft robot, composed exclusively of soft materials (elastomeric polymers), which is inspired by animals (e.g., squid, starfish, worms) that do not have hard internal skeletons." The robot is solely powered by relatively low pressures (10 psi), and controlled by 5 pneumatic actuators. The research was funded by DARPA."
Link to Original Source
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"Significant" Amounts of Water Found on the Moon

JoeRobe JoeRobe writes  |  more than 4 years ago

JoeRobe (207552) writes "Space.com and others are reporting on a story by NASA, in which they have found "significant" amounts of water ice on the moon as a consequence of NASA's LCROSS lunar impact mission. From the article, 'Based on the measurements, the team estimated about 100 kilograms of water in the view of their instruments — the equivalent of about a dozen 2-gallon buckets'."
Link to Original Source
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Naked Mole Rat Can't Get Cancer

JoeRobe JoeRobe writes  |  more than 4 years ago

JoeRobe (207552) writes "According to a new article in PNAS, the naked mole rat is found to be cancer impervious. As reported by ScienceNOW report: "The naked mole rat's cells hate to be crowded, it turns out, so they stop growing before they can form tumors....Normal human and mouse cells will grow and divide in a petri dish until they mash tightly against one another in a single, dense layer--a mechanism known as 'contact inhibition.' Naked mole rat cells are even more sensitive to their neighbors, the researchers found. The cells stop growing as soon as they touch. The strategy likely helps keep the rodents cancer-free, as contact inhibition fails in cancerous cells, causing them to pile up.""
Link to Original Source
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NASA Mars Phoenix is Dead

JoeRobe JoeRobe writes  |  more than 5 years ago

JoeRobe (207552) writes "After over 5 months of operation, NASA's Mars Phoenix lander has finally succumbed to the harsh Martian autumn. The lander's mission was originally scheduled for only 3 months. From the article: "As anticipated, seasonal decline in sunshine at the robot's arctic landing site is not providing enough sunlight for the solar arrays to collect the power necessary to charge batteries that operate the lander's instruments... The lander dug, scooped, baked, sniffed and tasted the Red Planet's soil. Among early results, it verified the presence of water-ice in the Martian subsurface, which NASA's Mars Odyssey orbiter first detected remotely in 2002." The article points out that while the lander may be dead, the enormous amount of data that it obtained will keep scientists busy for years."
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Most kids play video games

JoeRobe JoeRobe writes  |  about 6 years ago

JoeRobe (207552) writes "CNN is reporting that most kids (97%) play video games on a regular basis. From the story: "half of boys who were questioned listed a game with an "M" or "AO" rating as one of their favorites, compared with 14 percent of girls." However, the researchers are avoiding deeming gaming "good" or "bad". In fact, they found that "those who played games in face-to-face social settings were more likely to say they were committed to civic participation," possibly because gaming can make ties with other local gamers, which in turn stimulates "civic engagement.""
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NASA's Phoenix Finally Fills Oven

JoeRobe JoeRobe writes  |  more than 6 years ago

JoeRobe writes "Phoenix has successfully filled oven #4 of the Thermal and Evolved-Gas Analyzer instrument (TEGA). They have spent several days now vibrating the screen above the oven, trying to get a significant amount of soil sample into it. From the article: "the oven might have filled because of the cumulative effects of all the vibrating, or because of changes in the soil's cohesiveness as it sat for days on the top of the screen." Either way, this is the first step toward getting some interesting data from this instrument."
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