Comments of the Week #122: from distances in the Universe to the dangers of a parent comet

 “Failure I can live with. Not trying is what I can’t handle!” -Sanya Richards-Ross

It’s been a crazy week here at Starts With A Bang, including a pretty good meteor shower and some other rather remarkable stories. I just recorded a radio show with Dr. David Livingston of The Space Show this past Tuesday, and it's downloadable or available for streaming right here!

Screenshot from my 2016 episode of The Space Show, via http://www.thespaceshow.com/show/09-aug-2016/broadcast-2754-dr.-ethan-siegel. Screenshot from my 2016 episode of The Space Show, via http://www.thespaceshow.com/show/09-aug-2016/broadcast-2754-dr.-ethan-s….

I've confirmed with Forbes that yes, they swear they no longer block ad-blockers, and so if you're running one and it doesn't let you through, leave a comment for me and I'll pass it onto my senior editor. Miss anything this week? Check out all the great news:

There's a lot to look back on, so let’s dive into our comments of the week!

Public perception of whether crime rates are up as compared to one year ago (top line) vs. the actual crime victimization rate (bottom line). Image credit: Gallup's annual Crime survey, conducted Oct. 3-6, 2013. Public perception of whether crime rates are up as compared to one year ago (top line) vs. the actual crime victimization rate (bottom line). Image credit: Gallup's annual Crime survey, conducted Oct. 3-6, 2013.

From Denier about crime ticking upwards: "I can show hard evidence from neutral sources showing crime has ticked up and those with the short attention point of view do indeed have a point. I can transcribe text to show the point of a discussion was an opinion over appropriateness of tone rather than denying science. In the end it likely doesn’t matter because even with contrary evidence right in their face, people willfully won’t see it."

There's a lot that's been said already so I won't go over all of the old stuff, but there's an interesting thing to consider and digest here: whether short-term "upticks" in the data (or downticks, for that matter) are significant when talking about long-term trends. This is a question that should have a quantitative answer. It's a question where we should be able to look at things like "how much data do we need to know whether this uptick is meaningful or not?" You know, like we do with the climate science data.

Warming rate of the Earth, as of 2011, and how it changes depending on which start year you choose. Image credit: tamino of http://tamino.wordpress.com/2011/10/30/judith-curry-opens-mouth-inserts-foot/. Warming rate of the Earth, as of 2011, and how it changes depending on which start year you choose. Image credit: tamino of http://tamino.wordpress.com/2011/10/30/judith-curry-opens-mouth-inserts….

The conclusion for the climate data, by the way, is that if one wishes to pull out an accurate warming trend, one must take data sets in increments no smaller than 15-to-17 years. If crime is ticking upwards over a 3-month or 6-month period, how big is that uptick and how significant is it? Does this affect the overall trend, or is it consistent with a random fluctuation?

But perhaps it's only my opinion that asking scientifically meaningful questions like this is important when it comes to the data. Perhaps Newt is right, that when it comes to politicians and what garners them the most positive attention, it's much more about how people feel about what's happening than what's actually happening. Taking the cue from climate science, that appears to be absolutely the case. Maybe Kipling had it right when he wrote his famous epitaph for a dead statesman:

I could not dig: I dared not rob:
Therefore I lied to please the mob.
Now all my lies are proved untrue
And I must face the men I slew.
What tale shall serve me here among
Mine angry and defrauded young?
The GOODS-N field, with galaxy GN-z11 highlighted: the presently most-distant galaxy ever discovered. Image credit: NASA, ESA, P. Oesch (Yale University), G. Brammer (STScI), P. van Dokkum (Yale University), and G. Illingworth (University of California, Santa Cruz). The GOODS-N field, with galaxy GN-z11 highlighted: the presently most-distant galaxy ever discovered. Image credit: NASA, ESA, P. Oesch (Yale University), G. Brammer (STScI), P. van Dokkum (Yale University), and G. Illingworth (University of California, Santa Cruz).

From Michael Kelsey on distances in the Universe: "How do we _know_ the distances so far beyond standard candles? It seems to me that we get the redshift distance from z, and from that the redshift age. But converting redshift age into “true comoving distance” involves making the GR assumption. Is there any obvious observational way to independently confirm the GR curve? Is that what “angular diameter distance” does for us?"

You do have to make the GR assumption at some point, but only in the sense that there are different ways of measuring distance that depend on what the fabric of space has been doing. As the Universe expands, different distance measures depend on the redshift in different ways. If you measure the angular size of an object, for example, the angular diameter distance depends on the comoving distance divided by (1 + z). If you measure the brightness (luminosity) of an object, thought, the luminosity distance depends on the comoving distance multiplied by (1+z).

Various ways of measuring distance in the Universe. Image credit: Wesino at English Wikipedia. Various ways of measuring distance in the Universe. Image credit: Wesino at English Wikipedia.

Above, you can see the luminosity distance, the "naive Hubble" distance (just given by v/H), the comoving distance (different from the Hubble estimate) and, at bottom (skipping lookback time), the angular diameter distance. We have multiple methods that we can use on the same galaxy, and we get different results. In a non-GR Universe, particularly at high redshift, a well-understood single object is enough to falsify the notion that all these different measures yield the same answer.

The Bubble Nebula, also known as NGC 7635, is an emission nebula photographed here by the Hubble Space Telescope for its 26th anniversary. Image credit: NASA, ESA, Hubble Heritage Team. The Bubble Nebula, also known as NGC 7635, is an emission nebula photographed here by the Hubble Space Telescope for its 26th anniversary. Image credit: NASA, ESA, Hubble Heritage Team.

From PJ on the Bubble Nebula: "This looks like a long term pregnancy!"

I had never, ever thought of that before. I had called these new star-forming regions stellar nurseries before, but yes, the bluish coloration makes it look like it's filled with amniotic fluid and that there's some kind of stellar fetus inside.

The star powering the bubble itself, estimated at approximately 40 times the mass of the Sun. Image credit: NASA, ESA, Hubble Heritage Team. The star powering the bubble itself, estimated at approximately 40 times the mass of the Sun. Image credit: NASA, ESA, Hubble Heritage Team.

Just keep in mind, at some point -- perhaps while the bubble is still present -- this star will go supernova. But that's not a cosmic birth; it's an incredible cosmic death. Does that make this a cosmic miscarriage?

Image credit: James Beacham for the ATLAS collaboration, via his Twitter account. Image credit: James Beacham for the ATLAS collaboration, via his Twitter account.

From Denier on invisible particles: "If the LHC was creating new particles other than the ones already in the Standard Model, but those particles were sterile, would we know?"

When you make a new particle in a collider, you have to conserve both energy and momentum. Most collisions between particles are glancing, meaning each one maintains almost all of their original momentum. This is just fine, because we build our detectors with the intent of detecting particles with a large transverse momentum, meaning we focus on the rare collisions that not only hit each other head-on, but where a significant amount of the momentum happens to be transverse to the beam direction. This is why detectors have the shapes they do.

A sketch of the schematics of the CMS detector. The C stands for compact, which is hilarious because ATLAS, the other CERN detector is the ONLY particle detector in human history that's larger. Image credit: CERN. A sketch of the schematics of the CMS detector. The C stands for compact, which is hilarious because ATLAS, the other CERN detector is the ONLY particle detector in human history that's larger. Image credit: CERN.

There are a few different types of calorimeters inside to measure charged particles and their energies as well as photons; there are magnetic fields and ionization trackers to measure charges and momenta; there are the outer layers to measure muons, and then there's "missing energy." If we reconstruct both the missing energy and the missing momentum, we can determine whether these are light, ultra-relativistic particles like neutrinos, or whether they have a good sized rest mass and are sterile "other" particles, like WIMP dark matter. So far, we don't have any sterile particles, but those simple tasks -- measure the energy and momentum of everything that comes out and look for what's left over -- will give you the mass of a missing particle.

Image credit: The Marenostrum Numerical Cosmology Project, with acknowledgment to Arman Khalatian and Klaus Dolag. Image credit: The Marenostrum Numerical Cosmology Project, with acknowledgment to Arman Khalatian and Klaus Dolag.

From See Noevo on dark stuff: "What is the sigma up to for the existence of dark matter and dark energy?"

This depends incredibly strongly on which component of the data set you're looking at. If you look at interacting galaxy pairs, you get about a 3-sigma result. If you look at the rotation curves of an individual galaxy, you get around 5-sigma. If you look at supernovae for dark energy, you get 7-sigma. And if you look at single colliding galaxy cluster pair and the weak lensing data they provide, you get a 12-sigma result.

The Bullet Cluster, the first colliding galaxy clusters showing the separation between normal matter (pink, from the X-rays) and dark matter (blue, from gravitational lensing). Image credit: X-ray: NASA/CXC/CfA/M. Markevitch et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U. Arizona/D. Clowe et al. Optical: NASA/STScI; Magellan/U. Arizona/D. Clowe et al. The Bullet Cluster, the first colliding galaxy clusters showing the separation between normal matter (pink, from the X-rays) and dark matter (blue, from gravitational lensing). Image credit: X-ray: NASA/CXC/CfA/M. Markevitch et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U. Arizona/D. Clowe et al. Optical: NASA/STScI; Magellan/U. Arizona/D. Clowe et al.

But that's not the way we do science. We don't cherry pick one set of results; we look at the full suite! That means taking the best data sets from all available, reliable sources and combining them together to draw your conclusion. This has been done, as Michael Kelsey notes! If you look at the weak lensing, BAO, supernova and CMB data combined:

Baryon density (Ωb): 0.0486±0.0010
Dark matter density (Ωc): 0.2589±0.0057
Dark energy density (ΩΛ): 0.6911±0.0062

Which is to say, dark matter has about a 45-sigma significance, and dark energy has over a 100-sigma significance. This should impress anyone except the most fervent ideologue.

In a hypertorus model of the Universe, motion in a straight line will return you to your original location. Image credit: ESO and deviantART user InTheStarlightGarden, under a c.c.-by-s.a. 4.0 license. In a hypertorus model of the Universe, motion in a straight line will return you to your original location. Image credit: ESO and deviantART user InTheStarlightGarden, under a c.c.-by-s.a. 4.0 license.

From eric on returning to your starting point in the Universe: "Ethan takes on the case of whether you can do this in the current universe, but we can also consider it as a challenge to human engineering. I.e., can we build a curved space such that we can walk in a straight line and arrive back where we started? Here’s how.
Step 1: build a wormhole.
Step 2: walk in wormhole until you’re at the middle (well, at least away from the edge).
Step 3: make a left (or a right) 90 degree turn.
Step 4: walk in straight line.
You will arrive back where you started once you have traversed the circumference of the wormhole."

Ahh, the good old timelike geodesic for a slower-than-light observer. This is the lamest way to come back where you started; you could also get there by building a precise rocket that:

  1. launched you up into space,
  2. at speeds too slow to enter low-Earth orbit,
  3. so you'd fall back down to the planet's surface,
  4. but calculated so precisely so that you hit your launch location exactly.

But this is lame! This is a cop-out. If you want to really do this justice, you should be moving at the speed of light; you should be a null geodesic!

An infinitely repeating Universe would mean that someone could travel in a straight line and return to where they began. Image credit: V. Springel et al. and the Virgo Consortium/Millennium simulation, edited by E. Siegel. An infinitely repeating Universe would mean that someone could travel in a straight line and return to where they began. Image credit: V. Springel et al. and the Virgo Consortium/Millennium simulation, edited by E. Siegel.

And as for black hole/wormhole/gravitational slingshots, that's a cop-out, too. You should be looking to circumnavicate the Universe, and do this for real. Just as you could walk in a circle of any arbitrary size and claim "I went around the world!" and your skeptic friends could punch you for lying about the obvious meaning of "around the world," you could take a shortcut through the Universe to arrive back at your start point. But what's the point? Come out one side of the Universe and back inside the other, like the proposition intended!

The size of our visible Universe (yellow), along with the amount we can reach (magenta). Image credit: E. Siegel, based on work by Wikimedia Commons users Azcolvin 429 and Frédéric MICHEL. The size of our visible Universe (yellow), along with the amount we can reach (magenta). Image credit: E. Siegel, based on work by Wikimedia Commons users Azcolvin 429 and Frédéric MICHEL.

Sure, with dark energy, you might need a warp drive to do it, and I can support that kind of cheating. But defeating the premise and not learning whether the Universe is even topologically closed or not? That's a sad, cheating story.

The comet that gives rise to the Perseid meteor shower, Comet Swift-Tuttle, was photographed during its last pass into the inner Solar System in 1992. Image credit: NASA, of Comet Swift-Tuttle. The comet that gives rise to the Perseid meteor shower, Comet Swift-Tuttle, was photographed during its last pass into the inner Solar System in 1992. Image credit: NASA, of Comet Swift-Tuttle.

And finally, from Omega Centauri on comet Swift-Tuttle, and the energy it contains: "Ethan, I think you dropped a zero. In comparing kinetic energy versus the C-T impactor 2.6**3 *4**2 = 280, not 28."

There is actually a much more sophisticated way to calculate the energy of a potential impactor, and I didn't go into the details in the post, because... well, it's a pain in the neck! But for you, Omega, let's do it! The biggest difference between what the KT impactor was composed of (in assumptions) and what Swift-Tuttle appears to be is in terms of density. To calculate this, I used the traditional method given by Weissman, articulated here: http://www.cambridge.org/catalogue/catalogue.asp?isbn=9780521863452

A planetoid colliding with Earth, analogous (but larger and slower-moving) than an impact between Swift-Tuttle and Earth would be. Image credit: NASA / Don Davis. A planetoid colliding with Earth, analogous (but larger and slower-moving) than an impact between Swift-Tuttle and Earth would be. Image credit: NASA / Don Davis.

A radius of ~13 km and an estimated density of 600 kg/m^3 gives a cometary mass of ~6×10^15 kg. This is, interestingly enough, about an order of magnitude lower than an asteroid's density, which should be closer to 4,000-5,000 kg/m^3. An impact velocity of 61 km/s, which is approximately (3.8-4.0) times the impact velocity of the KT impactor yields an impact energy of 2.75×10^9 megatons. The dino killer was estimated at ~10^8 megatons, and so there's your factor of 28, not 280.

I'm actually on vacation, but you'd never know because I couldn't help but make sure there was no lag or drop-off in these articles for you, my dear readers. I'll read everything you say when I get back on the 21st, but in the meantime, enjoy the rest of what the Universe brings to you!

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@Ethan

there’s an interesting thing to consider and digest here: whether short-term “upticks” in the data (or downticks, for that matter) are significant when talking about long-term trends.
...
The conclusion for the climate data, by the way, is that if one wishes to pull out an accurate warming trend, one must take data sets in increments no smaller than 15-to-17 years.

The 17 year requirement from statistical significance in climate stems from the bounds of interannual variability of Earth's climate. The interannual variability of human behavior is vastly greater. You are right that it should have a quantitative answer but the example of climate terrible beyond use.

A far more instructive example is that of business trends. Let's say I run a company and my revenue has been down for the past 6 quarters (FY 2015 and 1H2016) and the revenue collapse is accelerating. Everyone can see the numbers.

If I addressed the problem by pointing out statistics from decades ago and supported it with a chart that conveniently cut off the past 3 years of corporate revenue it would rattle everyone. The corporate board, the shareholders, and the employees would call into question my ability to handle the problem. They'd be idiots if they didn't.

The business world if full of examples of dominant business that became irrelevant or even ceased to exist in incredibly short timescales. It helps to have great foresight but being slow to correct when you do goof is deadly simply because trends in human behavior are mercurial.

In the case of violent crime we're not talking about selling fewer widgets or employees losing jobs. We're talking about women being violated and people being shot and losing their life. Although I'm not hysterical, after a year and a half of an accelerating trend it would be nice if the people who were in the position of doing something about it didn't brush it off by saying all the additional people being hurt don't rise to the level of significance, or that only dark skinned people in urban areas are affected so it isn't a big deal.

“Just keep in mind, at some point — perhaps while the bubble is still present — this star will go supernova. But that’s not a cosmic birth; it’s an incredible cosmic death. Does that make this a cosmic miscarriage?”

Perhaps.
It certainly wouldn’t be a cosmic abortion.
Because, well, you know.

But I can only imagine the frequency and vehemency of your posts if it *was* an abortion...
‘How dare they target and deliberately destroy those precious, inanimate gas balls I’m so fond of!’

Perhaps your anger would be assuaged by assurances that such operations would be “safe, legal, and rare.”
(Although now she’s shortened it to just “Safe and legal.”)

By See Noevo (not verified) on 14 Aug 2016 #permalink

Me: “What is the sigma up to for the existence of dark matter and dark energy?”

Ethan: “If you look at interacting galaxy pairs, you get about a 3-sigma result… And if you look at single colliding galaxy cluster pair and the weak lensing data they provide, you get a 12-sigma result.”

Twelve sigma! A 1-in-about 100,000,000,000,000,000,000,000,000 likelihood that DM/DE does not exist.
That’s pretty comforting.

But I’d think you’d direct your focus to the weakest link in the chain, so to speak. That is, the 3-sigma result.

Question: If 3-sigma in this case means something like a 93.4% confidence in the existence of DM/DE, what is the thing or things represented by the 6.6%?
(I'm looking for an answer other than "not DM/DE".)

By See Noevo (not verified) on 14 Aug 2016 #permalink

I’ve confirmed with Forbes that yes, they swear they no longer block ad-blockers, and so if you’re running one and it doesn’t let you through, leave a comment for me and I’ll pass it onto my senior editor.

I find that the content is accessible (if very slow to load), but on my admittedly ancient platform, social-media logins don't work unless Ghostery is disabled, and neither does commenting.

In a sense, limiting functionality in the face of ad blockers would have made more sense from the get-go, but I'm not quite sure that's what's going on, as disabling it didn't work at all during the blockade, which seems not to have been field-tested before deployment.

On the other hand, what's more valuable, some crappy ad space or the information garnered from social-media logins?

@Ethan: Thank you! I guess I hadn't internalized that the relationships were that simple; somehow I thought some level of a(t) scale time-dependence had to be folded in.

From what you say, it sounds like directly comparing the luminosity distance (taking standard candles as correct) with the angular diameter distance, is enough to get the comoving distance directly. That's very cool.

By Michael Kelsey (not verified) on 14 Aug 2016 #permalink

The conclusion for the climate data, by the way, is that if one wishes to pull out an accurate warming trend, one must take data sets in increments no smaller than 15-to-17 years. If crime is ticking upwards over a 3-month or 6-month period, how big is that uptick and how significant is it? Does this affect the overall trend, or is it consistent with a random fluctuation?

A 3- to 6-month fluctuation in long term time series data does not, by itself, tell you anything, unless there has been some type of "shock" to the system generating the data, but even then there should be some indication that the change could generate such a change (a classic example was a dramatic drop in accident deaths on some major roads in Australia after mandatory seat belt laws were put in place, and enforced). This limited amount of data presents no evidence in favor of the beginning of an increase or against such an increase.

If 3-sigma in this case means something like a 93.4%

sn hasn't even mastered the normal distribution.

This should impress anyone except the most fervent ideologue.

See post numbers 2 and 3 above.

Which is to say, dark matter has about a 45-sigma significance, and dark energy has over a 100-sigma significance.

Ahem. It's not at all clear to me how one gets to reverse-engineer reported 1 σ uncertainties into "significance."

But I can only imagine the frequency and vehemency of your posts if it *was* an abortion…
‘How dare they target and deliberately destroy those precious, inanimate gas balls I’m so fond of!’

Perhaps your [imaginary] anger would be assuaged by assurances that such operations would be “safe, legal, and rare.”

And you have the temerity to piteously whine about being characterized as a troll?

From the death of old stars comes the birth of new, hence the long pregnancy.
:)

Has the whole Kubrick angle been played out yet? I block quite a bit of stuff.

Denier @1: I think you're missing the forest for the trees. Yes there is a recent uptick. But folks like Newt have been using the "crime is increasing" mantra for years; Ethan's first chart shows the public misperception is about 16 years old. Conservative pundits (and Trump) also regularly use of other, obviously empirically wrong claims (70 million out of work people! Obama tanked the economy!). This makes it fairly clear that the crime comments are simply part of a larger effort to make the current democratic administration look worse than it really is.

Sure, its possible Newt was making some opaque point about 2016 crime in Baltimore signaling a future rise. But I think its far more likely he was simply engaging in negative demagoguery, because that is what he and folks like him are wont to do. And if you need an olive branch, I'll say that liberal pundits often engage in demagoguery too. Both sides demagogue. Newt is one of the folks doing it. There is no need to try and create some torturous apologetic line of reasoning to make his comments appear accurate; Newt is just one example of the many partisan political drum-beaters - on both sides - for whom accuracy is not a major concern. And Ethan's point is completely valid - it should be more of a major concern.

Ethan:

But that’s not the way we do science. We don’t cherry pick one set of results; we look at the full suite! That means taking the best data sets from all available, reliable sources and combining them together to draw your conclusion.

SN's response to Ethan:

But I’d think you’d direct your focus to the weakest link in the chain, so to speak. That is, the 3-sigma result.

LOL.

SN:

If 3-sigma in this case means something like a 93.4% confidence in the existence of DM/DE, what is the thing or things represented by the 6.6%?

It doesn't represent any alternative hypothesis to DM, what it represents is the chance the measured quantity is different from what we measured it to be. Did you really not know that, or were you making a misleading point about statistics just to be rhetorical?

SN

You almost had it, so close. You seem to grasp that sigma values are shorthand for probabilities, but your grasp of probability theory is weak. The sigma values Ethan quoted are for independent tests of dark energy. When you have independent tests, the probabilities are multiplied; you don't just go with the "weakest link". That weakest link result combined with the other results further strengthens the evidence.

Consider a more mundane example. Suppose you have a coin that you suspect is unbalanced so that the probability of flipping heads is not 50%. We can't determine anything by a small number of flips, but for a large number we can make a statistical argument. We flip it 10000 times for example. Now we can predict the behavior of a fair coin and state that we expect an average of 5000 heads with a standard deviation of 50. We do the experiment and find that we got 5400 heads - an 8 sigma result.

An observer now wuestions whether you were maybe flipping the coin in a way that was biased and repeats the experiment. He gets 6100 heads, a 22 sigma result. Others do their own experiments and get 10, 12 and 15 sigma results.

Now it's my turn. By now you should be pretty strongly convinced that the coin is biased. You could even combine the past experiments to find a confidence level. I decide to repeat the experiment anyway, and I get 5150 heads, a 3 sigma result. Should we really start questioning our earlier conclusion? Is the probability of bias really only equal to that calculated from my experiment. Do tje other trials count for nothing?

This was kind of what I was hetting at with an earlier post to you. If the 3 sigma result is all you have, then it's certainly worth skepticism when you see conflicting data. If you have other more significant results, the 3 sigma one actually serves as further confirmation, and apparantly conflicting results will be much more highly scrutinized. It's not impossible to overturn an idea that has evidence at a 100 sigma level, but it's very difficult and unlikely.

All of which begs the question, what do you have against the idea of dark energy. I know your basic agenda is to call science into question because your pushing religion, but even disproving DE wouldn't help. Cosmologists (or ANY scientists) when faved with the falsification of the consensus idea will not just give up and say Goddidit. There would be a new scientific idea instead. You can't win support for your religious beliefs by disproving science.

Cosmologists (or ANY scientists) when faved [sic] with the falsification of the consensus idea will not just give up and say Goddidit. There would be a new scientific idea instead. You can’t win support for your religious beliefs by disproving science.

Creationism's contrived dualism* has (IMO) never had scientists as the primary target. Its all about the public: present laypeople (preferably kids) with a false binary choice between science and creationism,then appeal to their incredulity about some aspect of science, and hope that these two fallacious arguments together will convince the person to accept creationism. So my guess is SN isn't expecting to change Ethan's mind, rather he's hoping to change some lurker minds.

*For a discussion of this contrived dualism, see SCOTUS' decision in 1982's McLean case, or Jones' decision in 2005's Kitzmiller.

"f you measure the angular size of an object, for example, the angular diameter distance depends on the comoving distance divided by (1 + z). "

The hubble constant was calculated by another astronomer (name escapes me now) via the assumption that galaxies were all the same rough size (of a given shape), and calculated the hubble constant to a value much closer to that we agree on today than the one calculated at first from the redshifts.

"You are right that it should have a quantitative answer but the example of climate terrible beyond use."

Proclamations are refuted with the same method.

"In the case of violent crime we’re not talking about selling fewer widgets or employees losing jobs."

In the case we were talking about was the disconnect between the alarmism of "the man in the street" and actual reality. The fact you STILL don't deign to acknowledge this indicates you know you're standing on theoretical thin air.

"Although I’m not hysterical, after a year and a half of an accelerating trend "

By proclaiming an accelerating trend WHEN NO SUCH TREND HAS BEEN SHOWN, you ARE being hysterical

As we expected from a reactionary idiot like yourself.

To Sean T #13:

Regarding your flippin’ coin analogy,
in the real world, we can investigate the coin and can identify exactly WHAT is causing it to be biased. E.g. Too much nickel on one side of the nickel.

But what you have here, instead, is
the mystery of the “Dark Coin”.

And you call it science.

By See Noevo (not verified) on 15 Aug 2016 #permalink

Regarding your flippin’ coin analogy,
in the real world, we can investigate the coin and can identify exactly WHAT is causing it to be biased.

Are you going to dump a pail of trash over your head for an encore?

The issue of bias in coin flips is far more complicated than sn believes (no surprise there). His notion of "too much nickel" doesn't seem to hold water.

In light of all the variations, it is natural to ask if inhomogeneity in the mass distribution of the coin can change the outcome. [Lindley, 1981] followed by [Gelman & Nolan, 2002] give informal arguments suggesting that inhomogeneity doesn’t matter for flipped coins caught in the hand. Jaynes reports that 100 flips of a jar lid showed no evidence of bias. We had
coins made with lead on one side and balsa wood on the other. Again no bias showed up. All of this changes drastically if inhomogenious coins are spun on the table (they tend to
land heavy side up). As explained above, some of this bias persists for coins flipped onto a table or floor

from
http://statweb.stanford.edu/~susan/papers/headswithJ.pdf

But more importantly, here

But what you have here, instead, is
the mystery of the “Dark Coin”.

And you call it science.

again states that something he believes has to be false must be false, due to his belief. Once again, you see demonstrated the stifling that creationism brings to the human mind: if an area of science doesn't fit a particular belief then it is the science that si wrong, not the belief. No investigation needed.

if an area of science doesn’t fit a particular belief then it is the science that si wrong, not the belief

This is indeed the most depraved S.N. comment that I can recall going back for several weeks, even given that he was flailing to try to distract from being pantsed over the "weakest link in the chain" attempt.

I'm probably giving him too much credit but even the wording suggests an attempt to distract from what is fundamentally a teleological complaint:

in the real world, we can investigate the coin and can identify exactly WHAT is causing it to be biased

With three fewer words, this becomes "WHY it is." His internal model of causation could probably also be written up as as a case report in a psychology journal: the expansion of the universe is detectable, and so is deviation from a Bernoulli process an "unfair coin."*

Well, let's dial "the real world" back. It's still "real," right? There existed a time when metallurgy wasn't well understood and precision analysis of physical objects wasn't possible.**

So... in this era, how would S.N. react to such an observation? Stash the Holy Coin of Mystery away with St. Peter's head?

* I suspect that the "more nickel" routine emerged from an attempt to shoehorn the notion of "loaded dice" into the situation.
** Heaven help the standard kilogram.

^ I suppose burning its creator at the stake is another option.

But what you have here, instead, is
the mystery of the “Dark Coin”.

And you call it science.

Again, you're not thinking about the measurement correctly. The measurement to which the uncertainty refers is probably something like a mass measurement of the interacting galaxies. Here is an example. Dark matter is the theory or hypothesis that tells us why (heh) the measured mass is higher than what can be accounted for by baryonic matter.

IOW the "coin" here is a galaxy, which we directly observe through telescopes. Its not some invisible unknown, and studying it (and making hypotheses about why it behaves the way it does) is certainly science.

To eric #22:

“Dark matter is the theory or hypothesis that tells us why (heh) the measured mass is higher than what can be accounted for by baryonic matter. IOW the “coin” here is a galaxy, which we directly observe through telescopes. Its not some *invisible unknown*, and studying it (and making hypotheses about why it behaves the way it does) is certainly science.”

No.
So called Dark Matter is completely, 100%, “invisible unknown.”
“Dark Matter” is just a sciencey linguistic invention, really a placeholder, for the cause of something science doesn’t understand.

By See Noevo (not verified) on 15 Aug 2016 #permalink

One other thing, eric …

“… its all about the *public*: present laypeople (preferably kids) with a false binary choice between science and creationism, then appeal to their incredulity…”

There’s no choice between science and creationism.
There’s a choice between *evolution* and creationism.
(And as I’ve stated before, creationism doesn’t belong in any science class. But neither does evolution. Both could be taught in something like a philosophy class.)

Regarding teaching the kids, yes, the education establishment's key is to dumb them down early. Then, the chances of them remaining so as adults are better.
It’s working well.
One of countless examples:
https://www.youtube.com/watch?v=LWB8B614jac

By See Noevo (not verified) on 15 Aug 2016 #permalink

I presume that I'm missing some sort of idiotic Y—be embed in this rapidly decaying three-comment salvo.

“Dark Matter” is just a sciencey linguistic invention, really a placeholder, for the cause of something science doesn’t understand.

And? Exactly the same thing could be said about electrons.*

* Caveat: I found the this to be a tedious read, but the basic observations are sound. Tomonaga's The Story of Spin was much more engaging, but YMMV.

" those simple tasks … will give you the mass of a missing particle."

But they would give any information on the blast/shockwave that is produced by the collision in SpaceTime.

Think of gun shooting a bullet, creating a backlash AND producing a BLAST!

By Elle H.C. (not verified) on 15 Aug 2016 #permalink

Wow SN, I expect you to miss the point of my posts, but this time you have outdone yourself. Kudos.

The point had nothing to do with coins, dark matter or anything else like that. The point was that the mathematics of probability theory just don't work the way you think. It should be intuitively obvious (which is why I used the coin example) that the probability of a series of independent trials showing a seemingly nonrandom effect has a lower probability of occurring randomly than does the observation of a single nonrandom-seeming observation. Coins, measurements, whatever; it has no bearing on the math.

Now, I will try to explain this again. Scientifically, the existence of an entity is determined by the observable consequences of its existence. That is, if dark energy exists, certain observations can be made and these will have certain quantitative values. Ethan gave you a list of these observations and the probability that they are due to randomness (quite low). Therefore there is little doubt that the observations match up with what we would expect if dark energy exists. Therefore we conclude that it does in fact exist.

What you seem to be looking for is something akin to deductive proof of existence. Of course that's not necessary since the scientific community is quite willing to change its theories if new evidence is found.* As of now, with what we now know, dark energy gives the best explanation of observations. That may change in the future as more information is obtained.

*Just a note: don't confuse the scientific community with individual scientists. While the community as a whole will eventually embrace a new paradigm if warranted, it is far from rare that individuals will cling to an old, discredited one. Even the greatest of scientists are not immune. Einstein denied quantum mechanics. Mach never believed atomic theory. In fact, there was one philosopher of science (can't remember who it was - help please) who maintained that paradigm shifts in science really only occur when old scientists die off and are replaced by young scientists.

Wow Sean T, I expect you to miss the point of my posts (especially metaphors – “dark coin”), but this time you have outdone yourself. Kudos.

By See Noevo (not verified) on 16 Aug 2016 #permalink

In fact, there was one philosopher of science (can’t remember who it was – help please) who maintained that paradigm shifts in science really only occur when old scientists die off and are replaced by young scientists.

Are you thinking of Planck?

"A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it."

^ Sigh. Blockquote fail.

Nice try sn, but the notion that someone could misinterpret one of your massively simple comments isn't believable.

Wow Sean T, I expect you to miss the point of my posts (especially metaphors – “dark coin”)

This isn't a metaphor, you slobbering idiot.

There’s no choice between science and creationism.
There’s a choice between *evolution* and creationism.

Oh really? From Biology for Christian Schools (a fundie textbook): "The people who have prepared this book have tried consistently to put the Word of God first and science second." p. xi. Also on p. xi: "You may even find a 'scientific' explanation of the biblical locust (grasshopper) plague in Egypt...If the conclusions contradict the Word of God, the conclusions are wrong, no matter how many scientific facts appear to back them." Moving a bit further, on page 8: "Logic, observations, workability, common beliefs, or personal faith cannot disprove these claims of the Bible." Wow, they even go after logic!

Let's try another source, Biology: God's Living Creation. Teacher's guide, p.vi: "Biology, God's Living Creation...gives him [the student] an infallible source of truth - the Bible - with which to compare its observations." Hmmm...I must've missed the "compare observations with the bible" step when I was learning the methodology of science. That goes a lot deeper than just rejecting evolution.

Or how about the claims creationists put forth themselves in court documents? This is from McLean vs. Arkansas:

Creation-science includes the scientific evidences and related inferences that indicate: (1) Sudden creation of the universe, energy, and life from nothing; (2) The insufficiency of mutation and natural selection in bringing about development of all living kinds from a single organism; (3) Changes only within fixed limits of originally created kinds of plants and animals; (4) Separate ancestry for man and apes; (5) Explanation of the earth's geology by catastrophism, including the occurrence of a worldwide flood; and (6) A relatively recent inception of the earth and living kinds.

Three of those six are anti-TOE claims. But three of them are more general and attack geology and cosmology.

But hey, that was 1982. Clearly fundies have moved on! So let's go to Answers in Genesis current web page about science. Surely they don't attack science broadly! Let's see: "In a biblical worldview, scientific observations are interpreted in light of the truth that is found in the Bible. If conclusions contradict the truth revealed in Scripture, the conclusions are rejected." Wow, again, that's a methodological disagreement a heck of a lot deeper and broader than just 'evolution is wrong.'

I'm not saying you personally accept all these claims about science. But creationism as a movement has certainly attacked science writ large, not just evolution. The TOE draws the most creationist ire, but as these quotes show, creationists have taken issue with the fundamental empirical nature of science (claiming we should accept the bible when the two disagree), with geology, with cosmology, heck, even in some cases with the scientific explanation for why locust swarms occur.

[eric]the “coin” here is a galaxy, which we directly observe through telescopes. Its not some *invisible unknown*, and studying it (and making hypotheses about why it behaves the way it does) is certainly science.”

[SN]No.
So called Dark Matter is completely, 100%, “invisible unknown.”

No? You're just plain wrong here. The measurements to which the uncertainty applies are measurements of mass based on observation of galactic luminosity, EM spectra, and movement over time. Those are the measured quantities. If you disagree, tell me what *you* think the researchers measured.

@eric #11

I think you’re missing the forest for the trees.

It depends entirely on what point you are talking about. With regards to the Camerota-Gringrich interview, @Ethan is flat out wrong. I’m not saying Newt doesn’t engage in demagoguery or there is no existing other material which may make the point. I don’t care about the forest. I’m just noting an error in the analysis of this one tree.

If the point you are choosing to defend is that perceptions don’t always match reality and it proves the majority of people aren’t openly evaluating the full suite of information available before forming opinions, then of course it is true. I’m simply pointing out certain bits of evidence that indicate while we may argue about who is closest to the door it is plain that @Ethan is standing in the same tent with the rest of us. Well, the rest of us except @Wow. He’s in more of a padded cell than a tent but I think you get the gist.

I don’t care about the forest. I’m just noting an error in the analysis of this one tree.

Exactly. I couldn't agree more.

To eric #34:

Seenoevo: “There’s no choice between science and creationism. There’s a choice between *evolution* and creationism.”

Eric: “Oh really?”

Yes, really. “Creationism”, while it certainly can extend to the origin of the universe outside of life on earth, most often deals with questions of the origin of life and specifically the origin of man. In this sense, creationism is opposed NOT to science in general but rather to “evolutionary science” in particular.

However, as you say: “... That goes a lot deeper than just rejecting evolution.”
That’s a separate issue, but it’s funny, isn’t it, how one thing can lead to another?

All of a sudden, we go from a disagreement about the origin of man, to you and your kind *proclaiming as false* the many and varied fundamental beliefs of Christianity (i.e. miracles), including its MOST important: the PHYSICAL, BODILY RESURRECTION OF JESUS CHRIST.

Very funny.
And that’s one of the reasons I hammer away at the junk science of evolution.
(And also do some picking at other “gems” (e.g. cosmology’s dark matter/dark energy, multiverses; geology’s dating issues; paleontology’s 70 million year old soft tissues.).

Science sets itself up as the Wizard of Oz.
I like to peek behind the curtain.

By See Noevo (not verified) on 16 Aug 2016 #permalink

To eric #35:

Seenoevo: “No. So called Dark Matter is completely, 100%, “invisible unknown.””

Eric: “No? You’re just plain wrong here…The measurements …Those are the measured quantities.”

I wasn’t talking about the observable measurements nor the observable galaxy.
Nor the observable coin.
I was talking about NOT observing the THING that’s causing the “coin” to behave non-randomly.

If it’s not a completely, 100%, invisible unknown, why then is it called DARK matter?

By See Noevo (not verified) on 16 Aug 2016 #permalink

There’s no choice between science and creationism

correct. creationism (or, as oday's losers call it, intelligent design) is not science at all. So, if science is to be done, there is no choice: creationism/ID need not apply.
This applies, of course, to the intellectually honest, sn will still ignore facts.

paleontology’s 70 million year old soft tissues

You have had, at least 6 times, references and explanations provided to you explaining why there is no "issue" with the thing you misrepresent here. As you've been asked before, isn't there something in your mythology that says you shouldn't lie?

Dean,

Don't be an asshole and stop feeding the troll.

By Paul Dekous (not verified) on 16 Aug 2016 #permalink

I like to peek behind the curtain.

That's a keeper, but you could at least have spelled "peep" correctly.

Paul, do you mean sn or you, because you're doing a great job of trolling on your own.

Don’t be an asshole and stop feeding the troll.

I'd rank the content-free whinging about other people's comments as far more irritating than S.N.

SN + Dean + Narad = Troll squad :)

By Paul Dekous (not verified) on 16 Aug 2016 #permalink

sometime paul you'll need to explain how you are any different than the resident creationist sn.

“Troll” report through #47:

Posts by See Noevo = 9.
Posts to or about See Noevo = 23.
Other posts = 15.

By See Noevo (not verified) on 16 Aug 2016 #permalink

If it’s not a completely, 100%, invisible unknown, why then is it called DARK matter?

For the same reason the big bang is called the big bang; historical contingency.

Going back to the '90s, there have been a lot of different experiments observing different phenomena about large scale structure behavior. AIUI the ones relevant to this discussion all agree that galactic motions and structure, gravitational lensing, etc. are inconsistent with what we would predict based on the baryonic matter we know about operating within known laws of physics. Scientists want to understand why. So they started developing a whole bunch of hypotheses to test (and drop, and revise) to see which one might be right. The vast majority of these hypotheses can be separated into two broad categories: the first group is hypotheses that posit there is more mass than what we observe. The second set posits that gravity (or other fundamental forces) don't operate the way we expect them to on large scales.

Why call the first set 'dark matter' hypotheses? Because they posit the explanation for the observed mismatch is more matter, which does not emit detectable radiation. The phrase doesn't mean scientists are breaking the rules of science by positing fundamentally undetectable things. It just means we can't directly detect the stuff now. Scientists will continue to do theoretical work on DM hypotheses, making predictions that can be tested. Experimentalists will then run the tests. The results will leave some hypotheses on the cutting floor and others to be modified or accepted. All of which is perfectly normal science.

I think you've gotten way too wrapped around the axle trying to extract deep philosophical implications from what is basically a label - an appellation. But the label isn't the thing; the 'thing' here are the hypotheses being researched and tested, and they are very much within the normal boundaries of science.

To eric #49:

“The phrase [dark matter] doesn’t mean scientists are breaking the rules of science by positing fundamentally undetectable things. It just means we can’t directly detect the stuff now.”

Positing fundamentally undetectable [for now] things.
Like dark matter, dark energy, multiverses.
And maybe even what caused the big bang,
and what caused the laws that seem to govern our universe.

I see.
Just normal boundaries science.

By See Noevo (not verified) on 17 Aug 2016 #permalink

Like dark matter, dark energy, multiverses.

One of these things is not like the others, but it's not at all surprising that you can't be bothered to try to lower the entropy of the conceptual porridge sloshing around in your brainpan.

"It depends entirely on what point you are talking about. With regards to the Camerota-Gringrich interview, @Ethan is flat out wrong"

No he isn't. You can only create a personal "reality" where your assertion is true BY MAKING ETHAN'S CLAIM DIFFERENT FROM REALITY.

People are more then twice as scared of criminal violence than reality would support (TEXTBOOK ALARMISM!), and Newt is pandering to the ignorance rather than risk losing their vote and making them BETTER INFORMED.

And without a properly informed electorate, YOU CANNOT HAVE DEMOCRACY.

"SN + Dean + Narad = Troll squad"

Then refer back to paul's earlier "comments" and discover that this is nothing more than getting the claim in before it is leveled at you, you trolling moron.

@Wow #52

And without a properly informed electorate, YOU CANNOT HAVE DEMOCRACY.

The world you live on sounds nice. Here on Earth we have loads of stupid people and their vote counts just as much as a highly educated vote. Their democracies keep on keeping on.

To Denier #54:

“Here on Earth we have loads of stupid people and their vote counts just as much as a highly educated vote. Their democracies keep on keeping on.”

Until they don’t.

A fairly well-known quote:
"A democracy is always temporary in nature; it simply cannot exist as a permanent form of government. A democracy will continue to **exist up until the time that voters discover that they can vote themselves generous gifts from the public treasury.** From that moment on, the majority always votes for the candidates who promise the most benefits from the public treasury, with the result that every democracy will finally collapse over loose fiscal policy, (which is) always *followed by a dictatorship*.
The average age of the world's greatest civilizations from the beginning of history, has been about 200 years.”

Who knows, maybe Hillary can also be our first female dictator?

By See Noevo (not verified) on 18 Aug 2016 #permalink

Any surprise that the quote given by star troll sn is a mish-mash of dubious origin?

The following quotation has been attributed to Tytler, although it has also been occasionally attributed to Alexis de Tocqueville:[citation needed]

A democracy is always temporary in nature; it simply cannot exist as a permanent form of government. A democracy will continue to exist up until the time that voters discover that they can vote themselves generous gifts from the public treasury. From that moment on, the majority always votes for the candidates who promise the most benefits from the public treasury, with the result that every democracy will finally collapse due to loose fiscal policy, which is always followed by a dictatorship.
The average age of the world's greatest civilisations from the beginning of history has been about 200 years. During those 200 years, these nations always progressed through the following sequence: From bondage to spiritual faith; From spiritual faith to great courage; From courage to liberty; From liberty to abundance; From abundance to selfishness; From selfishness to complacency; From complacency to apathy; From apathy to dependence; From dependence back into bondage.
This text was popularised as part of a longer piece commenting on the 2000 U.S. presidential election, which began circulating on the Internet during or shortly after the election's controversial conclusion.

There is no reliable record of Alexander Tytler's having written any part of the text. In fact, it actually comprises two parts which didn't begin to appear together until the 1970s. The first paragraph's earliest known appearance is in an op-ed piece by Elmer T. Peterson in the 9 December 1951 The Daily Oklahoman, which attributed it to Tytler:

Two centuries ago, a somewhat obscure Scotsman named Tytler made this profound observation: "A democracy cannot exist as a permanent form of government. It can only exist until the majority discovers it can vote itself largess out of the public treasury. After that, the majority always votes for the candidate promising the most benefits with the result the democracy collapses because of the loose fiscal policy ensuing, always to be followed by a dictatorship, then a monarchy”.
The list beginning "From bondage to spiritual faith" is commonly known as the "Tytler Cycle" or the "Fatal Sequence". Its first known appearance was in a 1943 speech by Henning W. Prentiss, Jr., president of the Armstrong Cork Company and former president of the National Association of Manufacturers, delivered at the February 1943 convocation of the General Alumni Society of the University of Pennsylvania. The speech was subsequently published under the titles "The Cult of Competency" and "Industrial Management in a Republic".

@See Noevo #55

Who knows, maybe Hillary can also be our first female dictator?

All I can say is that you have quite an imagination but it would be fun to see Hillary in a Black Mamba Dictator Pantsuit.

https://www.youtube.com/watch?v=lAV1wBT-jwU

" And without a properly informed electorate, YOU CANNOT HAVE DEMOCRACY."

The world you live on sounds nice"

And if I said without euclidean space, pytharorean theorems would not hold, would you claim that the world I live on sounds nice?!?!?!?

WHERE DO I CLAIM A WORLDSYSTEM EXISTS???

I DIDN'T.

It is factually true that without an informed populace, you cannot have a democracy. Just like without euclidian space you cannot show that pythagoras was correct.

And what do you think your ridiculous dismissive comment was doing? Apart from make you feel better through arrogant ignorance?

"Here on Earth we have loads of stupid people and their vote counts just as much as a highly educated vote."

Irrelevant and orthogonal. For one, here on earth we have loads of people who are MISINFORMED taking part in democracy. Hence their intelligence is orthogonal to the facts here on planet earth. And it's irrelevant in that what we have on earth has nothing whatsoever to do with what is needed for an operable democratic system, whether intelligence or information. intelligence is helpful, but hardly required, but information, true information, ESSENTIAL.