private static UnboundDoubleFlag defineDoubleFlag(
            String flagId, double defaultValue, String description, String modificationEffect, Dimension... dimensions) {
        return Flags.defineDoubleFlag(flagId, defaultValue, OWNERS, toString(CREATED_AT), toString(EXPIRES_AT), description, modificationEffect, dimensions);
    }
Definition for permanent feature flags

@author bjorncs
flags/src/main/java/com/yahoo/vespa/flags/PermanentFlags.java