2649: Physics Cost-Saving Tips

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Physics Cost-Saving Tips

Title text: I got banned from the county fair for handing out Helium-2 balloons. Apparently the instant massive plasma explosions violated some local ordinance or something.

Explanation

This explanation may be incomplete or incorrect: Created by a FAUX VECTOR - Please change this comment when editing this page. Do NOT delete this tag too soon. If you can address this issue, please edit the page! Thanks.

This comic continues the previous comic 2648: Chemicals's jocular theme of tricks to supposedly save money based on misinterpretations of science. Here is a list of "cost-saving tips" which would seem to reduce a cost or provide something for free, allowing physicists to save money in their research.

• The prefix "pseudo-" refers to an inauthentic variation of something. Fakes are usually cheaper than their original brand-name product, while often working just as well, so the comic implies a pseudovector could be a less expensive substitute for a regular vector. On the contrary, pseudovectors, or axial vectors, are distinct alternatives to regular polar vectors, the former usually being involved with rotation or physical effects that share properties with rotation, similar to the relationship between angles and lengths. Pseudovectors are formed from the cross products of polar vectors, and while similar to polar vectors, there is no physical meaning to their specific direction, only their magnitude and portions of their position. For example, angular velocity is described by a pseudovector (labeled 'L' in the comic) normal to the plane of rotation, originating from the center of rotation, with magnitude proportional to the velocity ('ω') of rotation.

• Fourier analysis can decompose any periodic function into a series of sine waves. A square wave can thereby be represented as the sum of an infinite series of sine waves. However, the sine waves are not removed or separated individually, so such a Fourier transform does not produce a "supply" of sine waves for practical use in any tasks other than analysis, and as abstract mathematical objects exempt from the laws of supply and demand, their value is similarly limited.

• Chemical elements are identified by the number of protons in each atomic nucleus, equal to the number of electrons in their shell (unless the atom is ionized), which dictates most of their chemical behavior. Isotopes are variants of the element with different numbers of neutrons in the nucleus, among which chemical behavior is usually nearly identical. The comic suggests that the neutrons don't serve any useful purpose, so, in theory, if purchasing an element by weight, and its isotopes have the same price per unit weight, then you can save money by buying isotopes with no neutrons at all. In reality, the cost per unit weight for material containing a larger concentration of normally rare isotopes, such as heavy water or enriched uranium, is much higher than the cost of material containing isotopes in their ordinary proportions. (An exception is depleted uranium, which costs less than regular uranium because it is a waste product from the production of enriched uranium.) In addition, a certain range of neutron quantity is needed to keep atoms stable, as atoms with too many or too few neutrons will decay more quickly than the common isotopes.

The image shown is helium-2, an isotope of helium which has a half-life of less than a nanosecond. It decays into two protons, releasing a large amount of energy—hence the explosion mentioned in the title text. Helium balloons are often given out at county fairs and other similar events, but they are filled with helium-4, and therefore inert. If a balloon was filled with helium-2, as the title text suggests, the results would be immediately explosive. Handing out what are effectively bombs at a county fair would not go down well with local authorities, and therefore being banned from the fair is a very mild punishment. Criminal charges such as reckless endangerment or even attempted murder would be more likely, if it weren't for the sub-nanosecond fuse length rendering the scenario absurdly impossible.

• Free electrons are electrons that are not tightly bound to specific atoms so they can move freely, such as in conduction bands of the metallic bonds throughout the iron ingot depicted in the comic. Randall interprets "free" in a different sense, meaning no cost. The charges free electrons carry are electric, not monetary as implied by this pun.

Saving money from science experiments like this was also mentioned in 2007: Brookhaven RHIC.

Transcript

This transcript is incomplete. Please help editing it! Thanks.

[Title]

Physics Cost-Saving Tips

[A diagramatical spinning disc, at an angle]

[It is identified with an 'I', with a dotted axial arrow labelled 'L' and a rotational movement labelled 'ω' (small omega)]

[It sits on the left, and to the right of this is text...]

Try replacing regular vectors with pseudovectors whenever possible

[A square wave with three maxima (between four minima), and arrows pointing down into a collection of five sine waves of different wavelengths]

[One of the waves having the same frequency as the square wave and the rest of them are of shorter lengths with more peaks and troughs]

[It sits on the right, and to the left of this is text...]

A square wave can be broken down into an infinite supply of valuable sine waves

[Two atomic models]

[The left containing two protons (white with a "+" sign), two neutrons (black) and orbited by two electrons (small outlines, dotted orbits/movement lines), labelled below with the text of superscript atomic weight and element symbol]

⁴He

[The right model has just the two protons and the two electrons, labelled below with the text of an atomic weight and elemental symbol, and some subtext within brackets]

²He

(Decays fast - use quickly)

[Both models sit on the left of the comic, and to the right is text...]

Cut waste by buying lighter isotopes that don't have any dead-weight neutrons

[A flat rectangular bar, drawn in perspective with a scattering of dots/small circles on the top face and on the forward-facing one the label]

Iron

[An arrow points to the dots, from the text...]

Free electrons

[It sits to the right, and there is text to the left...]

Conductors are a great source of free electrons

(May carry charges)

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Discussion

I don't recommend trying to make your voice squeeky by breathing He-2. Barmar (talk) 19:57, 22 July 2022 (UTC)

But breathing a helium-rich mixture in general... so long as it still has sufficient oxygen in it ...I would speak highly of it! 162.158.34.221 20:27, 22 July 2022 (UTC)

Please link comic 2007. I tried to do so myself but the edit errored.172.70.86.34 22:17, 22 July 2022 (UTC)

The vandals are going rather hard today. Can we get the first few semi-protected or something please? SqueakSquawk4 (talk) 22:24, 22 July 2022 (UTC)

I think I've fixed it. At least, it was fixed when I left this comment. I also don't do much wiki editing on anything, so I hope I actually fixed it and didn't break anything in the process. EDIT: Not sure if editing comments is appropriate, but it's just before 7AM UTC and it seems the vandalism has stopped. I think I had to fix it twice after I originally left this comment NErDysprosium (talk) 06:37, 23 July 2022 (UTC)

They're back. Semi-protecting may work (though at a cost in useful edits); if any of the major contributors to this site know tricks to track down the physical location of an editing IP, that might open up other approaches. 172.70.230.3 03:33, 24 July 2022 (UTC)

They're going after templates and similar infrastructure pages. Banning the little klanshit's username would be a good first action. 172.69.71.30 03:40, 24 July 2022 (UTC)

Are the "charges" that free electrons carry implied to be monetary or criminal? 162.158.2.219 22:27, 22 July 2022 (UTC)

Fundamental particles have dipole-matic immunity. 172.70.211.88 01:47, 23 July 2022 (UTC)

Somone needs to rewrite that section on heavy water / enriched uranium... deuterium in heavy water has more neutrons (so fits the comics description), and u235 is actually neither the lower nor upper neutron count for natural uranium so also questionably fits the description. I would but my head hurts after trying to parse it 108.162.221.79 11:20, 23 July 2022 (UTC)

Is it worth mentioning the L and omega displayed in the first illustration are in conflicting directions (not following the right hand rule…)?172.70.210.145

How sinister! 172.70.91.80 19:28, 23 July 2022 (UTC)

Done, including a video proving Randall is right-handed, so that can't be the reason. 172.70.206.163 07:45, 24 July 2022 (UTC)

I disagree with the calculation of the energy of the ²He filled balloon: ²He -> H + H + 1.25MeV (Wikipedia). One Balloon is approx. 30-40l, i.e. approx 2 moles = 2 Avogadro Number = 1.2e24 Atoms of ²He. This means 1.2e24*1.25MeV = 1.9E24MeV = 3e11J = 71 ton of TNT (@4.2e9J/ ton of TNT (Wikipedia)). That is much less than a kiloton of TNT, but probably above the limit for recreational fireworks. The balloon might pop, too.

Agreed; corrected. 172.70.211.88 09:15, 24 July 2022 (UTC)

I have done my own calculations, and come to a number of roughly 18 tons of TNT. I have put my calculations on my profile, and linked it. Please comment there if you disagree. Thanks! SqueakSquawk4 (talk) 13:37, 24 July 2022 (UTC)

The statement "This would make the Helium-2 balloon-bomb the most powerful human-made non-nuclear explosion ever" would seem to be inaccurate, given that it is not actually a non-nuclear explosion. Should this be edited? 172.70.110.135 03:43, 24 July 2022 (UTC)

Deleted the sentence. 172.70.211.88 04:43, 24 July 2022 (UTC)

How much yield would a Helium-2 baloon have, anyway? I've seen "Lots", "2 kilotonnes" and "70 tonnes". Does anyone know how to calculate it once and for all, and leave a citation trail?

I just had a small search around, and can't seem to find the decay energy of helium-2. Does anyone even know how to calculate this???} SqueakSquawk4 (talk) 11:24, 24 July 2022 (UTC)

Scroll up a couple threads. 172.69.34.32 11:02, 24 July 2022 (UTC)

I didn't see that. I'm doing my own calculations now anyway. SqueakSquawk4 (talk) 11:24, 24 July 2022 (UTC)

I have done my own calculations, and come to a number of roughly 18 tons of TNT. I have put my calculations on my profile, and linked it. Please comment there if you disagree. Thanks! SqueakSquawk4 (talk) 13:37, 24 July 2022 (UTC)

Great! I replied to you there. 172.70.207.8 14:40, 24 July 2022 (UTC)

Fantastic what-if on electrons. I love the idea that making the moon out of electrons would create a naked singularity with the mass of the universe. 172.70.211.134 07:47, 26 July 2022 (UTC)

Dear Simulation Operator(s), please do not try that. 172.70.211.134 08:45, 28 July 2022 (UTC)

Could the title text potentially be a play on "ordinance" and "ordnance" (the latter of which refers to explosions)? 172.69.34.18 21:58, 31 August 2022 (UTC)