Sure, but mortgage interest can easily be enough to make that worth it without any other deductions. With $300K principal and a 5% loan, that’s $15K - about the same as a single taxpayer’s standard deduction and roughly half of a married couple’s standard deduction.

I don’t think gravitational waves traveling at the speed of light is the same as the gravitational attraction being apparently felt faster than light travels.

I don’t know how you would measure gravitational waves without measuring gravitational attraction.

It’s not light that is “communicating” that attraction.

Nobody said it was. The “speed of light” isn’t about “light”. Gravity propagates at the same speed, aka “c.”

This Reddit discussion on r/AskPhysics might help clear up your misconceptions. Notably:

Just to clarify: when people talk about the speed of gravity, they mean the speed at which changes propagate. It’s the answer to questions like: if I take the Sun and wiggle it around, how long does it take for the Earth to feel the varitation in the force of gravity? And the answer is that changes in gravity travel at the speed of light.

But that’s not what you’re asking about. Whenever you’re close to the Earth, gravity is always acting on you: it’s not waiting until you step off a cliff, like in the Coyote and the Roadrunner. The very instant your foot is no longer on the ground, gravity will start to move it downwards. The only detail is that it takes some time for it to build up an appreciable speed, and this is what allows us to do stuff like jump over pits: if you’re fast enough, gravity won’t be able to accelerate you enough - but gravity is still there.

I get the sense that you’re thinking about the second scenario when objecting to the concept that gravity travels at the speed of light.

https://bigthink.com/hard-science/speed-of-gravity/

I primarily use Standard Notes. It’s a fantastic tool and I can use it anywhere, online or offline. It’s not great for collaboration, though, and it doesn’t have a canvas option. But I use it for scratch pads, for todo lists, for project tracking, for ideas, plans, plotting for my tabletop (Monster of the Week) game, software design and architecture, for drafting comments, etc…

Standard Notes also has a ton of options for automated backups. I get a daily email with a backup of my notes; I can host my notes on my home server and the corporate one; I can also set up automated backups on any desktop.

I don’t use it for saving links. I’m still using Raindrop.io for that, even though I’m self-hosting both Linkding and Linkwarden.

For sharing and collaboration, I either publish to Listed with Standard Notes or use Hedgedoc, which is great for collaboration and does a great job presenting nodes, too.

For canvas notes, I use GoodNotes on a tablet or the Onyx Boox’s default Notes app. I’d love a better FOSS, self-hosted option, especially for the Boox, but my experiences thus far have been negative (especially on the Boox).

I’ve been trying out SilverBullet lately, since I want to try out cross-note querying and all that, but I’m too stuck in my habits and keep going back to Standard Notes. I think I’ll have better luck if I choose one app and go with it.

I also have a collection of Mnemosyne notebooks that I use with fountain pens (mostly the Lamy 2000, but also quite commonly a Platinum 3776 or a Twsbi). Side note: the Lamy 2000 was my first fountain pen and after getting it I went deep into fountain pens. I explored a ton of different options, found a lot of nice pens across a number of brands… and yet how I still haven’t found something that I consistently like more. The Pilot VP is great but deceptive; a fancy clicky pen that only holds 30 minutes of ink (in a converter, at least) is decidedly inconvenient.

I’ve also been checking out Obsidian on my work computer. So far I haven’t seen anything that makes me prefer it over my existing set of tools.

Hedgedoc is fantastic. If you’re okay with your notes app being web-only (without an app or even a PWA) and you don’t need canvas notes or multi-note queries, you should check it out.

First, every note is Markdown, but it supports a ton of things natively. It has native Vim, Emacs, and Sublime (the default) editors and it’s built to be great for collaboration (if you want).

It also has

• syntax highlighting for a ton of languages
• Mermaid.js support
• LaTeX support
• easy drag and drop image uploads
• a solid mobile interface (for a webapp in your browser, at least)
• built in revision history
• support for other diagram tools, like graphviz, flowchart.js
• a bunch of other little Markdown enhancements that make using it feel oddly intuitive

And best of all, they have a Hedgehog for the icon! (I may be biased.)

I’m familiar with SSL in the context of webdev, where SSL (well, TLS) is standard, but there the standard only uses server certificates. Even as a best practice, consumer use cases for client certificates, where each client has a unique certificate, are extremely rare. In an app, I would assume that’s equally true, but that shared client certificates - where every install from Google Play uses the same certificate, possibly rotated from version to version, and likewise with other platforms, like the App Store, the apk you can download from their site, F-Droid, if they were on it, and releases of other apps that use the same servers, like Molly. Other platforms might share the same key or have different keys, but in either case, they’re shared among millions of users.

I’m not sure Signal does have a client certificate, but I believe they do have a shared API access key that isn’t part of the source code, and which they (at least previously) prohibited the use of by FOSS forks (and refused to grant them their own key)

That said, I reviewed that code, and while I’m not a big fan of Java and I’m not familiar with the Android APIs, I’m familiar with TLS connections in webdev, the terms are pretty similar cross-language, and I did work in Java for about five years, but I didn’t see anything when reviewing that file that makes me think client certificates are being generated or used. Can you elaborate on what I’m missing?

Clearly they’re cosplaying as a Canonical engineer whose internal explanation and pleas for them to not take this approach fell upon deaf ears /j

you’re the only one with your SSL keys. As part of authentication, you are identified. All the information about your device is transmitted. Then you stop identifying yourself in future messages, but your SSL keys tie your messages together. They are discarded once the message is decrypted by the server, so your messages should in theory be anonymised in the case of a leak to a third party. That seems to be what sealed sender is designed for, but it isn’t what I’m concerned about.

Why do you think that Signal uses SSL client keys or that it transmits unique information about your device? Do you have a source for that or is it just an assumption?

If you’re a C developer who doesn’t know Rust, no.

And it’s I who should take a course in encryption and cybersecurity.

Yes. I was trying to be nice, but you’re clearly completely ignorant and misinformed when it comes to information security. Given that you self described as a “cryptography nerd,” it’s honestly embarrassing.

But since you’ve doubled down on being rude, just because I pointed out that you don’t know what you’re talking about, it’s unlikely you’ll ever learn enough about the topic to have a productive conversation, anyway.

Have fun protecting your ignorance.

If a communication norm is just about other people’s preferences, why should they change? Who’s to say that other people’s preferences are more important than their own, particularly given that this particular preference is shared by millions of other people.

If inconsistent use of capitalization actually hinders understanding for some subset of their audience, then that’s a different story. My experience is that people are more likely to be annoyed than to actually have issues understanding all lowercase text. All caps text, on the other hand, is a different matter - and plenty of government and corporate entities are fine putting important text in all caps. But all caps text is a known accessibility issue. When I search for “all lowercase accessibility,” though, all I get is a bunch of results saying to not use all caps text for accessibility reasons.

If you have sources showing that all lowercase text is an accessibility concern, then you should share them. Heck, you should have led with that. But as it is, your argument ultimately boils down to “someone else should change what they do, that works for them, because it annoys me.”

Nice try FBI.

Wouldn’t “NSA” or “CIA” be more appropriate here?

Well, if my pin is four numbers, that’ll make it so hard to crack. /s

If you’re using a 4 number PIN then that’s on you. The blog post I shared covers that explicitly: “However, there’s a limit to how slow things can get without affecting legitimate client performance, and some user-chosen passwords may be so weak that no feasible amount of “key-stretching” will prevent brute force attacks” and later, “However, it would allow an attacker with access to the service to run an “offline” brute force attack. Users with a BIP39 passphrase (as above) would be safe against such a brute force, but even with an expensive KDF like Argon2, users who prefer a more memorable passphrase might not be, depending on the amount of money the attacker wants to spend on the attack.”

If you can’t show hard evidence that everything is offline locally, no keys stored in the cloud, then it’s just not secure.

If you can’t share a reputable source backing up that claim, along with a definition of what “secure” means, then your claim that “it’s just not secure” isn’t worth the bits taken to store the text in your comment.

You haven’t even specified your threat model.

BTW, “keys” when talking about encryption is the keys used to encrypt and decrypt,

Are you being earnest here? First, even if we were just talking about encryption, the question of what’s being encrypted is relevant. Secondly, we weren’t just talking about encryption. Here’s your complete comment, for reference:

I have read that it is self hostable (but I haven’t digged into it) but as it’s not a federating service so not better than other alternative out there.

Also read that the keys are stored locally but also somehow stored in the cloud (??), which makes it all completely worthless if it is true.

That said, the three letter agencies can probably get in any android/apple phones if they want to, like I’m not forgetting the oh so convenient “bug” heartbleed…

Just so you know, “keys” are used for a number of purposes in Signal (and for software applications in general) and not all of those purposes involve encryption. Many keys are used for verification/authentication.

Assuming you were being earnest: I recommend that you take some courses on encryption and cybersecurity, because you have some clear misconceptions. Specifically, I recommend that you start with Cryptography I (by Stanford, hosted on Coursera. See also Stanford’s page for the course, which contains a link to the free textbook). Its follow-up, Crypto II, isn’t available on Coursera, but I believe that this 8 hour long Youtube video contains several of the lectures from it. Alternatively, Berkeley’s Zero Knowledge Proofs course would be a good follow-up, and basically everything (excepting the quizzes) appears to be freely available online.

it wouldn’t be very interesting to encrypt them, because now you have another set of keys you have to deal with.

The link I shared with you has 6 keys (stretched_key, auth_key, c1, c2, master_key, and application_key) in a single code block. By encrypting the master key (used to derive application keys such as the one that encrypts social graph information) with a user-derived, stretched key, Signal can offer an optional feature: the ability to recover that encrypted information if their device is lost, stolen, wiped, etc., though of course message history is out of scope.

Full disk encryption also uses multiple keys in a similar way. Take LUKS, for example. Your drive is encrypted with a master key. You derive the master key by decrypting one of the access keys using its corresponding pass phrase. (Source: section 4.3 in the LUKS1 On-Disk Format Specification (I don’t believe this basic behavior was changed in LUKS2).)

Its impossible to verify what code their server is running.

Signal has posted multiple times about their use of SGX Secure Enclaves and how you can use Remote Attestation techniques to verify a subset of the code that’s running on their server, which directly contradicts your claim. (It doesn’t contradict the claim that you cannot verify all the code their server is running, though.) Have you looked into that? What issues did you find with it?

I posted a comment here going into more detail about it, but I haven’t personally confirmed myself that it’s feasible.

Both of the reasons you’ve provided are nonsensical:

• It isn’t performed automatically if you disable it, and they did (and explained why)
• They said they don’t believe capitalization aids with clarity. They didn’t express the same opinion about punctuation and paragraph breaks.

I can’t use signal.

Why? Do you not have a phone number? Is it blocked in your country? Are you legally prohibited from using software with end to end encryption?

The sender ('s unique device) can with 100% accuracy be appended to the message by the server after it’s received.

How?

If I share an IP with 100 million other Signal users and I send a sealed sender message, how does Signal distinguish between me and the other 100 million users? My sender certificate is encrypted and only able to be decrypted by the recipient.

If I’m the only user with my IP address, then sure, Signal could identify me. I can use a VPN or similar technology if I’m concerned about this, of course. Signal doesn’t consider obscuring IPs to be in scope for their mission - there was a recent Cloudflare vulnerability that impacted Signal where they mentioned this. From https://www.404media.co/cloudflare-issue-can-leak-chat-app-users-broad-location/

404 Media asked daniel to demonstrate the issue by learning the location of multiple Signal users with their consent. In one case, daniel sent a user an image. Soon after, daniel sent a link to a Google Maps page showing the city the user was likely in.

…

404 Media first asked Signal for comment in early December. The organization did not provide a statement in time for publication, but daniel shared their response to his bug report.

“What you’re describing (observing cache hits and misses) is a generic property of how Content Distribution Networks function. Signal’s use of CDNs is neither unique nor alarming, and also doesn’t impact Signal’s end-to-end encryption. CDNs are utilized by every popular application and website on the internet, and they are essential for high-performance and reliability while serving a global audience,” Signal’s security team wrote.

“There is already a large body of existing work that explores this topic in detail, but if someone needs to completely obscure their network location (especially at a level as coarse and imprecise as the example that appears in your video) a VPN is absolutely necessary. That functionality falls outside of Signal’s scope. Signal protects the privacy of your messages and calls, but it has never attempted to fully replicate the set of network-layer anonymity features that projects like Wireguard, Tor, and other open-source VPN software can provide,” it added.

I saw a post about this recently on Lemmy (and Reddit), so there’s probably more discussion there.

since the sender is identified at the start of every conversation.

What do you mean when you say “conversation” here? Do you mean when you first access a user’s profile key, which is required to send a sealed sender message to them if they haven’t enabled “Allow From Anyone” in their settings? If so, then yes, the sender’s identity when requesting the contact would necessarily be exposed. If the recipient has that option enabled, that’s not necessarily true, but I don’t know for sure.

Even if we trust Signal, with Sealed Sender, without any sort of random delay in message delivery, a nation-state level adversary could observe inbound and outbound network activity and derive high confidence information about who’s contacting whom.

All of that said, my understanding is that contact discovery is a bigger vulnerability than Sealed Sender if we don’t trust Signal’s servers. Here’s the blog post from 2017 where Moxie describe their approach. (See also this blog post where they talk about improvements to “Oblivious RAM,” though it doesn’t have more information on SGX.) He basically said “This solution isn’t great if you don’t trust that the servers are running verified code.”

This method of contact discovery isn’t ideal because of these shortcomings, but at the very least the Signal service’s design does not depend on knowledge of a user’s social graph in order to function. This has meant that if you trust the Signal service to be running the published server source code, then the Signal service has no durable knowledge of a user’s social graph if it is hacked or subpoenaed.

He then continued on to describe their use of SGX and remote attestation over a network, which was touched on in the Sealed Sender post. Specifically:

Modern Intel chips support a feature called Software Guard Extensions (SGX). SGX allows applications to provision a “secure enclave” that is isolated from the host operating system and kernel, similar to technologies like ARM’s TrustZone. SGX enclaves also support a feature called remote attestation. Remote attestation provides a cryptographic guarantee of the code that is running in a remote enclave over a network.

Later in that blog post, Moxie says “The enclave code builds reproducibly, so anyone can verify that the published source code corresponds to the MRENCLAVE value of the remote enclave.” But how do we actually perform this remote attestation? And is it as secure and reliable as Signal attests?

In the docs for the “auditee” application, the Examples page provides some additional information and describes how to use their tool to verify the MRENCLAVE value. Note that they also say that the tool is a work in progress and shouldn’t be trusted. The Intel SGX documentation likely has information as well, but most of the links that I found were dead, so I didn’t investigate further.

A blog post titled Enhancing trust for SGX enclaves raised some concerns with SGX’s current implementation, specifically mentioning Signal’s usage, and suggested (and implemented) some improvements.

I haven’t personally verified the MRENCLAVE values for any of Signal’s services and I’m not aware of anyone who has (successfully, at least), but I also haven’t seen any security experts stating that the technology is unsound or doesn’t actually do what’s claimed.

Finally, I recommend you check out https://community.signalusers.org/t/overview-of-third-party-security-audits/13243 - some of the issues noted there involve the social graph and at least one involves Sealed Sender specifically (though the link is dead; I didn’t check to see if the Internet Archive has a backup).

Message history won’t be fully fixed. It can’t be without storing message backups in some cloud somewhere (whether it’s to iCloud, Google Drive, Dropbox, or Signal’s servers) and Signal omits its message history from system backups on iOS and Android.

iOS users are completely incapable of backing up their message history in the event of their phone being lost, stolen, or broken. This omission isn’t justified in any way, as far as I’m aware; I don’t know of any technical reason why following the exact same process as on Android wouldn’t work.

Android users are able to back up locally via Signal, but that isn’t on by default, can’t be automated, needs to be backed up separately, requires you to record a 30 digit code to decrypt it, and has limitations on when it can be used for a restore (can’t restore on iOS, for example). See https://support.signal.org/hc/en-us/articles/360007059752-Backup-and-Restore-Messages for more details.

Message history on linked devices - meaning iPads and desktop computers - is being improved, but it still won’t mean that a user who loses or trades in their phone as they get a new phone will be able to simply restore their phone from a system backup and restore their Signal message history. And even that isn’t anywhere near as easy as on Telegram, where a user can just log in with their password and restore their message history, no backup needed.

It’s great that they’re improving the experience for linked devices, but right now that doesn’t actually help if you lose, break, or trade in your phone. Maybe they’ll later allow users to restore to a phone from a linked device or support backups on iPhones, but right now the situation with message history isn’t just an unfriendly UX, but one that is explicitly and intentionally unreliable for a huge portion of Signal’s user-base.

Also read that the keys are stored locally but also somehow stored in the cloud (??),

Which keys? Are they always stored or are they only stored under certain conditions? Are they encrypted as well? End to end encrypted?

which makes it all completely worthless if it is true.

It doesn’t, because what you described above could be fine or could have huge security ramifications. As it is, my guess is that you’re talking about how Signal supports secure value recovery. In that case:

1. The key is used to encrypt your contacts, profile name, group avatars, social graph, etc., but not your messages.
2. Your key is only uploaded to the cloud if you have a recovery PIN or passphrase
3. Your key is encrypted using your PIN or passphrase using techniques (key-stretching, storing in server secure enclaves) that make it more difficult to brute force

The main criticism of this is that you can’t opt out of it without opting out of the Registration Lock, that it necessarily uses the same PIN or passphrase, and that, particularly because it isn’t clear that your PIN/passphrase is used for encryption, users are less likely to use more secure pass phrases here.

But even without the extra steps that we can’t 100% confirm, like the use of the Secure Enclave on servers and so on, this is e2ee, able to be opted out by the user, not able to be used to recover past messages, and not able to be used to decrypt future messages.

The concern is valid, and it has caused a lot of distrust in many companies due to the Snowden leaks, but that distrust is founded in the leaks.

Snowden explicitly endorsed Signal, too - and as far as I know he’s never walked that endorsement back.

https://signal.org/blog/sealed-sender/ explains the feature.

https://github.com/signalapp/Signal-Android/issues/13842 has some links into the code base showing where sealed sender is implemented.