I think the parent is more correct than you are?

The frequency does not provide an indication of load. The frequency can be 60.00Hz with 20,000 MW load in Ontario or with 10,000MW.

Changes in frequency provide a measure of changes in the balance between generation and load.

The generator’s prime mover’s governor has a droop function set so that typically a 5% change in frequency will result in a 100% change in output. This is how most generators on the grid arrest changes in frequency, but they would not restore the frequency to 60Hz. The droop allows for a steady state frequency error.

A handful of special generators are used to restore the frequency to 60Hz or balance the generation and load in an area.

The precise frequency does not matter, if one generator thinks the frequency is 59.99 and another thinks it is 60.01 their outputs will only be a little higher and lower than their load setpoint. It does not matter if they share changes in load perfectly evenly, so long as generators on the system in bulk respond according to their capabilities.

This article is wrong, or at least the headline and intro is wrong.

You don't need a precise time source to make power grids possible. You don't need any time source at all, as generator operators simply synchronise with the grid's current frequency (and phase) before throwing the switch that electrically connects the generator to the grid. And once the generators are connected, they are automatically locked to the exact same frequency and phase. It's not possible for them to fall out of phase without the electrical connection being broken (If you try to force a generator out of phase, it will draw more current trying to get back in phase and will eventually blow a fuse)

For engineering reasons, it's useful to keep the frequency within a few percent of a standard, but for most purposes, it doesn't matter if the grid is running at 58Hz, 60Hz or 62Hz and you can achieve way more accuracy with crude mechanical governor. Many simpler backup generators use nothing more than a mechanical governor to maintain their frequency.

The primary reason why power grids used accurate master clocks is actually the secondary reason that this article mentions: Automated time synchronisation.

This predates the days of modern quartz clocks. It was possible to make very precise mechanical clocks (especially for navigation use), but they were impractical and too expensive for every day use. The average clock or pocket watch would gain or lose several minutes per day and required constant manual adjustment. Loud bells ringing each hour would allow a town or small city to keep the same time, but different towns would be out of sync with each other.

There were various competing solutions at this time. Clocks would be synchronized over long distances with time signals transmitted over telegraph or radio. Paris actually had a network of pneumatic tubes that drove synchronised clocks driven with a pulse of air every minute: https://www.amusingplanet.com/2022/02/the-pneumatic-clocks-o...

But the power grid neatly solved this problem.

Not only did it distribute power, but it distributed a synchronised time signal across the entire nation. Your complicated mechanical wall clock could be replaced by a simple electric synchronous motor that drove the clock hands and it would keep perfect sync with every other clock on the same power grid.

All you needed to make this useful was a single master clock that kept the power grid running at exactly 60Hz (well, it actually drifts as load varies, but they deliberately vary it so there are exactly 5184000 pulses per day).

This time keeping service that power companies supplied as a secondary effect of their primary purpose was typically mandated by government regulations, as cheap and accurate synchronized time is a boost to the economy.

The physical markets are in New Jersey.

Not sure what they do in Chicago, but only derivatives are traded there; the spot markets for stocks are all in/around New York.

I’m sure the article is total wrong about the tax incentives like you say, but ICE AND NYSE had their colocation center and servers in New Jersey, not Georgia. They don’t have servers in GA except maybe for the printers in their office.

https://www.ice.com/fixed-income-data-services/access-and-de...

> There is no such thing as support/resistance in reality.

Where would you say 80% of the daily trade volume comes from on average?

The powers to be that I can think of:

institutional investors / fund managers slowly reallocating (selling stuff off, buying stuff) daily

high frequency trading algorithms trading shares back and forth to each other in an artificial way to generate synthetic volume/movement

market makers reacting to option chain volume to remain neutral

"hedge funds" / "quant funds" running their algorithm

what do those algorithms look for at the "minute by minute" scale if not things like support/resistance/patterns/volume?

Nice, thanks. I wonder by how much. Here is why I ask:

a lot of technical analysis is done on psychological levels related to (in my opinion) SPY strike prices/SPX strike prices/SPX levels.

Yet, /ES is typically 20 points ahead of SPX. For example, there can be a battle zone of support/resistance at 4900 on SPX, but /ES blew past it a day ago. I wasn't sure if one had more power/prominence than the other.

Slightly related: what are "big players" more likely to do to get exposure to the S&P directionally:

1. SPY shares long/short on margin/leverage

1. SPY options

1. SPX options

1. /ES e-mini futures

1. a blend of all

Does one trump another in popularity?

If you need both good measurements that should by ample margin be audible transparent, as well as enough power for virtually any headphone save those that need a special amplifier (electrostats like STAX's), you'll find it hard to go under $200.

This device is actually a gem for the price, and most popular recommendations will go higher in price and give you less. I have been there and done the digging, you're welcome to repeat the process.

At some point, new devices or new prices will change this. But, as far as I am aware, this is how it is right now.

I'm trying to understand what is the difference between this and using TLA.

For example, what is the difference between "robust theoretical basis of the Temporal Logic of Actions (TLA)" and "state-of-the-art static analysis"?

Sorry, I'm not an expert in TLA, but I thought that static analysis was basically what it was used for.