# Bronstein Timing

Keywords: Tournament

## Definition

Bronstein Timing is the time system where

• one gets an amount of time (for example, 10 minutes),
• one loses the time spent beyond a bonus time (for example 10 seconds)
• no time is added or deleted if moved inside bonus time

In other words: during the move the clock is counting down and after the move a bonus time is added, but at most the time which was used for the move, i.e. time_add = min ( time_used , bonus_time ). Thus the main time after each move decreases or stays the same.

## Delay Timing:

There is a slightly different time system, known as Delay Timing (or "time delay"), which just has different parameters, but is in practice the same time system.

In Delay Timing the main clock waits a certain amount of time (bonus time), before it starts counting down. So the bonus time is effectively granted before the move.

The two timing systems are related by the formula:

Br(m+b,b) == DelayTiming(m,b),

with:

m = main time and

b = bonus time

## Diagrams (Bronstein Timing)

Example 1 (more time than bonus time used)

```|----------------|       Time before move
```
```|-----|          :       Time at end of move
```
```      |------|   :       Bonus time
```
```|------------|   :       Time for next move
```

Example 2 (less time than bonus time used)

```|----------------|       Time before move
```
```|------------|   :       Time at end of move
```
```             |---:---|   Bonus time
```
```|----------------|   :   Time for next move
```
```                 |sss|   Spilled time
```

This system is therefore spilling.

## Diagrams (Delay Timing)

Example 1 (more time than delay time used)

```|----------------|         : Time before move
\                \
\                \
|ddd|-----------------|    : Time with delay
```
```|------------I        :    : Time used
```
```             |--------|    : Time for next move (excluding delay time)
```

Example 2 (less time than delay time used)

```|----------------|         : Time before move
\                \
\                \
|ddd|-----------------|    : Time with delay
```
```|-| :                 :    : Time used
```
```  : |-----------------|    : Time for next move (excluding delay time)
```
```  |s|                      : Spilled time
```

## Difference to Fischer Timing

The "but" part ("but the added time is at most ..") is the difference to Fischer Timing:

• in Fischer Timing, the remaining time can grow
• in Bronstein Timing, the remaining time cannot grow

## Example (Bronstein Timing)

10 minutes plus 30 seconds bonus.

```  #    Time     Used
------------------
1    10:00    1:00
2     9:30    5:00
3     5:00    4:00
4     1:30    0:10
5     1:30    0:20
6     1:30    0:30
7     1:30    1:30
8     0:00    lost
```

Note: In Bronstein Timing the bonus is added after the moves (with clock counting down main time during moves).

In Step 7/8 "zero time" is reached, it is game over, and no bonus time is added anymore.

In general, a state with less than bonus time remaining (at the begin of a move) is impossible to reach in the Bronstein Timing System - unless the clock has these parameters already at the begin of the game.

### Discussion (time delay, formula)

On "time delay":

ab?: This is a slightly different definition (which i would actually prefer): a additional "bonus clock" is used, which first counts down the bonus time, and after that switches to the main clock. The bonus is thus provided "before" the move (which makes a difference!).

Question: is there a equivalence to Bronstein timing via different parameters, like TimeDelay(m,b) = Br(m+b,b) ? i am not sure ... (note: from quote below the formula is probably not correct)

willemien: I don't play chess but i thought that since 2008 Fischer timing was the standard see http://main.uschess.org/content/view/7752/28/ rulebook changes 5F1, I guess that the old rulebook was written(2003) with analog clocks in mind and delay timing was therefore the only practical method. (this is about chess)

I think TimeDelay(m,b) is equal to Br(m+b,b) but it is purely theoretical. I think the quote you refer to is contrived the normal bonustime is 30 seconds not just 2.

ab?: No, i mean TimeDelay(m,b) != Br(m+b,b) because in Bronstein it can happen you have 23 seconds on the clock for every remaining move, but such a state is impossible in Delay Timing (assuming bonus time=30 sec), so they are not the same.

willemien Explain how I, under Bronstein timing, can have less than 30 seconds at the start of the move? (assuming you mean unequal with !=)

ab?: You set the initial main time to a lower number than the bonus time :) - otherwise you're right it cannot happen. So i change my opinion again - the equation is true :)