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List all build-in physical constants in Mathematica 11.3?

Posted 3 months ago
10 Replies
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Hi all

Is there a way to list all physical constants of the Quantity package? A list as provided in the deprecated reference would be great!


10 Replies

What you used to do is

<< PhysicalConstants` 

And then check list all the names in the Context[] they are in (or, as you say, edit the .m). You can probably still find and use the .m from an older version of Mathematica if you have a registered copy.

I cannot say the same about packlets I really haven't worked with them. It seems if you got a whole packlet (not just a value from one), they would be findable by using Context[] and Names[].

Unsure why you'd want "a whole list" since republishing them as a set is likely not allowed.

Posted 3 months ago

This post,, contains a manually curated list of the constants that are defined as units in the Quantity framework.

Posted 3 months ago

Same question posted here.


The following is a link to download a Mathematica UnitsHelper application. Its main palette has drop down menus for all the Mathematica physical constants, also all the units sorted alphabetically or by magnitude and that will paste into your notebook. Also links to all the Mathematica units help pages and NIST pages. There are also extra routines for implementing reduced units such as atomic units or geometrical units.

UnitsHelper Download

You could try whether the FormulaLookup feeded with the newly accepted fundamental constants following As of Today, the Fundamental Constants of Physics (c, h, e, k, NA) Are Finally… Constant! delivers all known data. This can be considered as the systematic, canonical way.

Hi all,

why not simply e.g.

EntityValue["PhysicalConstant", {"Name", "Value"}]

or am I misunderstanding the question? Regards -- Henrik

Posted 3 months ago

In Mathematica, you may enter Quantity["earth's gravity"] and get a valid result. However, I haven't found "earth's gravity" anywhere. The function call provided by you doesn't deliver that quantity either.

You didn't find it because of unstructered querying, Given that earth is a planet

In[2]:= PlanetData["Earth", "Gravity"]
Out[2]= Quantity[9.80, ("Meters")/("Seconds")^2]

Quantity[] is the answer, not the question. Given the huge set of possibilties the infamous free text input is a great testing facility (needs a working Internet connection because it queries Wolfram|Alpha):

enter image description here

this gives the idea to search within the planets, not directly within the quantities. In fact Quantity[] is Mathematica's way to express a number with an unit (physical, chemical, social, …) as one expression.

Ah, you mean

In[3]:= Quantity["earth's gravity"]
Out[3]= Quantity[1, "StandardAccelerationOfGravity"]

then you can

In[9]:= QuantityForm[
 Quantity[1, "StandardAccelerationOfGravity"], "LongForm"]
Out[9]//QuantityForm= StringForm["`1` `2`", 1, "standard acceleration \
due to gravity on the surface of the earth"]

In Quantity it reads

Supported units include all those specified by NIST Special Publication 811.

And here it is

In[25]:= Take[
 EntityValue["PhysicalConstant", {"Name", "Value"}], {187, 187}]

During evaluation of In[25]:= Quantity::unkunit: Unable to interpret unit specification EddingtonConstant4.

During evaluation of In[25]:= Quantity::unkunit: Unable to interpret unit specification ElectronProtonElectricGravitationalForceRatio.

During evaluation of In[25]:= Quantity::unkunit: Unable to interpret unit specification (SpeedOfLight)^2/(MONDConstant).

During evaluation of In[25]:= General::stop: Further output of Quantity::unkunit will be suppressed during this calculation.

Out[25]= {{"standard acceleration of gravity", 
  Quantity[196133/20000, ("Meters")/("Seconds")^2]}}

For the sake of diversity it has four different textual representations

  • standard acceleration of gravity
  • StandardAccelerationOfGravity
  • standard acceleration due to gravity on the surface of the earth
  • g

see QuantityForm.

Posted 3 months ago

Ahh!!! Thank you very much, now I understand. That answers (indirectly) my question. Thank you!

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