dnd 5e – Are the “Touched” feats’ spells ever subject to a spellcaster’s class rules (such as regarding preparation, components, and focuses)?

The Fey Touched and Shadow Touched feats published in Tasha’s Cauldron of Everything each grant the use of two spells. Among other things, they say:

  1. You learn the [spells].
  2. You can cast each of these spells without expending a spell slot [once per long rest].
  3. You can also cast these spells using spell slots you have of the appropriate level.

The spellcasting ability for these spells is specific to the feat, so it may or may not be the same as the ability of the class that granted the spell slots.

My question applies to both feats and all spellcasting classes, but for the sake of clarity consider an artificer who has taken Fey Touched, which grants Misty Step. Artificers must add the M component to all spells they cast using the artificers’ spellcasting feature, but #2 above has nothing to do with their feature so shouldn’t require that. That’s good, because the reason the artificer can teleport is their prior exposure to the Fey, not some magical widget.

However, things get more complicated when they’re casting Misty Step as described in #3, because the artificer’s spell slots do come from their spellcasting feature. In that case, does the artificer simply use the spell slot as “fuel” and otherwise cast the spell exactly as it had been cast for #2? Or is this inherently different, for which we must assume the artificer studied the Misty Step effect and replicated it with a widget?

If the former, we can assume the spell never needs to be prepared; if the latter, it almost certainly does need to be prepared like all artificer spells.

Also, Misty Step is not on the Artificer Spell List, but the Invisibility spell granted by Shadow Touched is. Would that alter the answer in any way?

Potentially Related:

Does Magic Initiate allow the chosen spell to effectively be “always prepared” if the spell is on their spell list?

What makes a spell being cast considered to be a {class} spell?

If a spellcaster’s racial trait grants a spell that requires material components, can they use their class’ focus to cast that spell?

dnd 5e – Can an Elder Oblex be subject to an AoE more than once?

The Elder Oblex has the Sulfurous Impersonation feature which lets it create an impersonation of a creature in another space. The feature goes on to state:

For all practical purposes, the simulacrum is the oblex, meaning the oblex occupies its space the simulacrum’s space simultaneously.

In the likely event that the Oblex has multiple simulacrums on a battlefield, what happens if 2 or more of them are subjected to an area of effect spell like fireball? Does the answer change for a wall spell like Blade Barrier?

mathematical optimization – Most efficient way to maximize value over 84 possibilities, each one subject to 3 linear inequalities

Let $0 < u < v < w < 10$ be natural numbers. I want to maximize $r$ across all choices of $u, v, w$ subject to the inequalities $(42 – 100 r) – (6 – 10 r)(w + v) + vw(1 – r), -(42 – 100 r) + (6 – 10 r)(w + u) + uw(1 – r), (42 – 100 r) – (6 – 10 r)(u + v) + vu(1 – r) ge 0.$ For example, $(u,v,w)=(4,5,6)$ should give $r le 4/15$ (this is the 1st $(u,v,w)$ I guessed, but it doesn’t have to be the best), and now we need $83$ more values. Without the natural numbers condition, I got a working command but the resulting expression was ugly. I added the conditions, but now the command failed:

 {Maximize({r, (42 - 100 r) - (6 - 10 r)*(w + v) + v*w *(1 - r) >= 
      0 && -(42 - 100 r) + (6 - 10 r)*(w + u) + u*w *(1 - r) >= 
      0 && (42 - 100 r) - (6 - 10 r)*(u + v) + v*u *(1 - r) >= 0, 
    0 < u < v < w < 10  , u (Element) PositiveIntegers , 
    v (Element) PositiveIntegers , w (Element) PositiveIntegers  }, 

Is there any way to do things more efficiently so that the command doesn’t fail? If it’s possible, I would also like to know how to return the values of $u, v, w$ which achieve the maximum.

I just tried

f(u_, v_, w_) := 
 Maximize({r, (42 - 100 r) - (6 - 10 r)*(w + v) + v*w *(1 - r) >= 
     0 && -(42 - 100 r) + (6 - 10 r)*(w + u) + u*w *(1 - r) >= 
     0 && (42 - 100 r) - (6 - 10 r)*(u + v) + v*u *(1 - r) >= 0}, r)

so that I could call

Maximize({f (u, v, w), 0 < u < v < w < 10, 
  u (Element) PositiveIntegers, v (Element) PositiveIntegers, 
  w (Element) PositiveIntegers}, {u, v, w})

next, but when I defined f, I got the output $Failed.

Update: I get

Maximize({{4/15, {r -> 4/15}}, True, True, True, True}, {4, 5, 6})

after defining the function and calling the last code snippet. Certainly, Mathematica can’t have read my mind and have known that I already did the case $(4,5,6)$ and got $4/15,$ so I’m tempted to believe that the first value I tried really did give the maximum. But why does Mathematica output $Failed for every input then? The function declaration had $Failed, and this output had $Failed off to the side.

reference request – What are some fields of research in mathematics that are not listed in the Mathematics Subject Classification (MSC) that should be included?

This is similar to a question I posed on Stack Exchange: https://math.stackexchange.com/questions/3887207/request-for-list-of-fields-of-research-or-fields-already-well-known-not-in-the.

I was browsing the Mathematics Subject Classification (MSC) scheme when I read from a few sources that there are some fields of research such as quantum algebra, trigonometry, and Lie theory (excluding Lie groups) that don’t have many related branches (if any) in the classification scheme. So, I was wondering if further examples of such fields that one may be interested in could be provided here?

This will be helpful to people looking to carry out research in one of these stated fields in the future. Thanks!

modified – Email Alerts with dynamic subject on add and edit items to the list

I want to send email alert with dynamic subject

  1. When a new item is added ,the subject of the email alert must be ‘New item added’.
  2. When i edit that item,the subject of the email should be ‘Item Modified’

How can i achieve this in a single workflow

i have checked the condition
if currentItem:created equals currentItem:modified
then email_message(a new variable) will be ‘New Item Added’
email_message will be Item Modified

Any help would be appreciated.Thanks.

Page subject has two names.

Hello, my page subject has two names (both names mean the same) , both names have search volume which I want to target, should I put them both in the H1? Example , Hot Cakes – Pancakes
Currently I have it .com/Hot-Cakes-Pancakes/ , is this confusing Google ? Should I just have one of the in the h1? If yes how do I add the second name, I want to cover both with the same page. I have many pages like this currently.

thanks for any input

certificates – CA cert with many Subject Alternative Name (SAN) entries, versus individual certs in public production?

The idea of using SANs makes sense if you have, for example, one web server which takes care of several smaller websites (e.g. example.com and internal.example.com). In this case, having one certificate per web server, with SANs for each website reduces the amount of configuration overhead.

However, once you start to create what I like to call a “megacertificate”, meaning once certificate with uncountably many SANs, you will run into problems. This certificate, and its associated private key, will likely be distributed to many many different servers, meaning that your private key will be in many different places.

This in turn means that the attack surface has now grown exponentially, as it means one compromised server can now compromise all domains, even if they are on different physical servers.

(+) its easier to standardise the certificate options (i.e. hashing/cyphers) on a shared cert

This is false. First of all, the certificate itself does not define any cryptographic ciphers to be used by TLS, only which cryptographic operations are necessary to validate the certificate.

This means that two different physical servers – let’s call them alice.com and bob.com – can use the same certificate (with SAN entries for both), and yet still support completely different sets of ciphers. alice.com could support only state-of-the-art ciphers and bob.com may be stuck using insecure legacy ciphers for interoperability reasons.

The only valid reason I can think of at the moment why you might use SANs – aside from convenience during manual setup – is that an appliance or application may not support uploading several different certificates, yet needs to serve different domains.

megapixels – Does higher MP magnify the subject?

The standard meaning of magnification ratio has to do with the physical size of the object and the physical area of the image plane (film/sensor) that it occupies when recorded.

E.g. if 1cm on a ruler is recorded occupying 1cm on the sensor then it is at a 1:1 magnification ratio. I.e only 3.5cm can be recorded on a FF (35mm wide) sensor due to the magnification)… MP’s do not affect that. Nor does sensor size (e.g. only 2.4cm can be recorded on an APS (24mm wide) sensor at 1:1).

Edit to answer comment: “The magnification I am thinking is “more detail” as in taking a picture of a newspaper from a distance, does a higher MP camera see the characters clearer?”

That is the resulting recorded resolution and not magnification/magnification ratio per se. The resulting recorded resolution depends on which aspect of the imaging chain is the limiting factor.

For instance, a lens set to f/11 can only project ~ 16MP onto a full frame sensor (median/green wavelengths). And that lens resolution could be reduced to say 14MP if the sensor has an anti-aliasing filter over it. And the recorded resolution could be farther reduced to 12MP if that is the resolution of the sensor.

But in this example the recorded resolution cannot be greater than 16MP regardless of the sensor resolution because the lens would still be the limiting factor. Conversly, a lens set to f/2.8 can (theoretically) project 240MP onto a FF sensor, in which case the sensor (AA filter) will be the limiting factor.


What are the different types of spam that the Lightning Network is subject to?

There are three types of spam problem in the Lightning Network. Let’s call them “local”,”fast” and “slow”.

Local spam is someone sending or requesting too much data: that’s a simple batter of code with rate limiting etc.

Fast spam is sending many failed payments. You can’t tell what will succeed and you can’t blame the sending peer (they may not be the source). This attack is free since we only pay on success. The answer is to require an up-front payment but it has to be small (making sure your incentive is to succeed) and it should not leak information on where you are in the path. I’ve been unable to find a scheme I’m happy with though, see my latest attempt here.

Slow spam is sending a long-lived payment. This consumes capacity > 1000x expected for a normal payment and is similarly free (if you fail). The only solution I like here is to penalize slow payments by requiring proof-of-channel closure but you can’t always tell if the payment was really in the channel and what if the close transaction pays super-low fees / conflicts? You need a Merkle tree of claimed HTLCs, plus onion unwrapping, agreement on valid closes, handling of fake Merkle trees… all possible but real work.

Summary: We can mitigate some attacks but real fixes need spec improvements and implementation. More attention from Smarter People Than Me (hi!) will help us here.

This question was answered by Rusty Russell on Twitter.