Maass oldforms

[jwj61]

From feedback for the page http://www.lmfdb.org/L/ModularForm/GL2/Q/Maass/4f5692c588aece2afe000001/

I'm not sure this is an error, but it is a confusion to me.

The above link to the $L$-function of the Maass form of level 6 and $R=5.09874190873$ seems strange, as this Maass form is actually comes from level 3 (with same $R$) linked below, and the $L$-function given just modifies the Euler factor at 2 (and I'm not sure the functional equation is then as stated).

http://www.lmfdb.org/L/ModularForm/GL2/Q/Maass/4f55571b88aece241f000013/

On the holomorphic side, you require newforms. For Dirichlet characters you take primitive ones. Why is the Maass case different? Maybe I missed the pulldown window where it was explained.

Note, there was no name or e-mail on this feedback, but it is one of three left in short succession, the last of which was by tobygee@fastmail.com

[davidfarmer]

This is the same error as in issue #2645

The Maass forms with the larger levels are wrong and should be deleted.

[AndrewVSutherland]

@davidfarmer Can you quantify that statement? If you can tell me exactly which forms need to be deleted I can remove them from the postgres database so that they will no longer be visible on web.lmfdb.xyz (which we plan to point www.lmfdb.org to sometime in the next few weeks).

[davidfarmer]

If an eigenvalue, R, occurs for two different levels, then that is very likely to be an error. If also the coefficients are equal for primes that do not divide the level, then that certainly is an error. When that occurs, one level will divide the other level, and the Maass form with the larger level should not be in the database. (You can think of it as an "old form", if that helps.) These issues can arise when searching for Maass forms, but it is a known problem and should have been addressed before the data was uploaded. Note that checking for equality of eigenvalues or coefficients is only up to the precision of the data. A few digit equality on R and simultaneously a couple digit equality on a couple coefficients is unlikely to give a false positive on the available data.

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On Wed, 26 Dec 2018, Andrew Sutherland wrote: @davidfarmer Can you quantify that statement? If you can tell me exactly which forms need to be deleted I can remove them from the postgres database so that they will no longer be visible on web.lmfdb.xyz (which we plan to point www.lmfdb.org to sometime in the next few weeks). — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.[AAM6LFozzX2txJ9fof4KLnDSRM-2698gks5u85KogaJpZM4ZhG-u.gif]

[AndrewVSutherland]

@davidfarmer I really need a more precise answer to my question of Dec 26 before I can take action. Can you give me a list of levels or a list of labels for the Maass forms that should be deleted? Alternatively, a python function that takes a maass_id and returns a boolean indicating whether the form should be deleted or not would be fine.

[davidfarmer]

It is the relationship between different entries that indicates there is a problem. I suggest we discuss this in person, which we can do soon. I'll poke around a bit more before then.

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On Thu, 7 Mar 2019, Andrew Sutherland wrote: @davidfarmer I really need a more precise answer to my question of Dec 26 before I can take action. Can you give me a list of levels or a list of labels for the Maass forms that should be deleted? Alternatively, a python function that takes a maass_id and returns a boolean indicating whether the form should be deleted or not would be fine. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.[AAM6LN-1ZSVFUqzkCVc4_4YhcY95NcaMks5vUUQ1gaJpZM4ZhG-u.gif]

[AndrewVSutherland]

Merging this issue with #2645 (I will copy Toby Gee's comment there).